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Why Old Physics Still Matters
By Chad Orzel, Forbes, 7/30/18
(The following is an approximation of what I will say in my invited talk at the 2018 Summer Meeting of the American Association of Physics Teachers. They encourage sharing of slides from the talks, but my slides for this talk are done in what I think of as a TED style, with minimal text, meaning that they’re not too comprehensible by themselves. So, I thought I would turn the talk into a blog post, too, maximizing the ratio of birds to stones…
(The full title of the talk is Why “Old Physics” Still Matters: History as an Aid to Understanding, and the abstract I sent in is:
A common complaint about physics curricula is that too much emphasis is given to “old physics,” phenomena that have been understood for decades, and that curricula should spend less time on the history of physics in order to emphasize topics of more current interest. Drawing on experience both in the classroom and in writing books for a general audience, I will argue that discussing the historical development of the subject is an asset rather than an impediment. Historical presentation is particularly useful in the context of quantum mechanics and relativity, where it helps to ground the more exotic and counter-intuitive aspects of those theories in a concrete process of observation and discovery.
The title of this talk refers to a very common complaint made about the teaching of physics, namely that we spend way too much time on “old physics,” and never get to anything truly modern. This is perhaps best encapsulated by Henry Reich of MinutePhysics, who made a video open letter to Barack Obama after his re-election noting that the most modern topics on the AP Physics exam date from about 1905.
This is a reflection of the default physics curriculum, which generally starts college students off with a semester of introductory Newtonian physics, which was cutting-edge stuff in the 1600s. The next course in the usual sequence is introductory E&M, which was nailed down in the 1800’s, and shortly after that comes a course on “modern physics,” which describes work from the 1900s.
Within the usual “modern physics” course, the usual approach is also historical: we start out with the problem of blackbody radiation, solved by Max Planck in 1900, then move on to the photoelectric effect, explained by Albert Einstein in 1905, and then to Niels Bohr’s model of the hydrogen atom from 1913, and eventually matter waves and the Schrodinger equation, bringing us all the way up to the late 1920’s.
It’s almost become cliche to note that “modern physics” richly deserves to be in scare quotes. A typical historically-ordered curriculum never gets past 1950, and doesn’t deal with any of the stuff that is exciting about quantum physics today.
This is the root of the complaint about “old physics,” and it doesn’t necessarily have to be this way. There are approaches to the subject that are, well, more modern. John Townsend’s textbook for example, starts with the quantum physics of two-state systems, using electron spins as an example, and works things out from there. This is a textbook aimed at upper-level majors, but Leonard Susskind and Art Friedman’s Theoretical Minimum book uses essentially the same approach for a non-scientific audience. Looking at the table of contents of this, you can see that it deals with the currently hot topic of entanglement a few chapters before getting to particle-wave duality, flipping the historical order of stuff around, and getting to genuinely modern approaches earlier.
There’s a lot to like about these books that abandon the historical approach, but when I sat down and wrote my forthcoming general-audience book on quantum physics, I ended up taking the standard historical approach: if you look at the table of contents, you’ll see it starts with Planck’s blackbody model, then Einstein’s introduction of photons, then the Bohr model, and so on.
This is not a decision made from inertia or ignorance, but a deliberate choice, because I think the historical approach offers some big advantages not only in terms of making the specific physics content more understandable, but for boosting science more broadly. While there are good things to take away from the ahistorical approaches, they have to open with blatant assertions regarding the existence of spins. They’re presenting these as facts that simply have to be accepted as a starting point, and I think that not only loses some readers who will get hung up on that call, it goes a bit against the nature of science, as a process for generating knowledge, not a collection of facts.
This historical approach gets to the weird stuff, but grounds it in very concrete concerns. Planck didn’t start off by asserting the existence of quantized energy, he started with a very classical attack on a universal phenomenon, namely the spectrum of light emitted by a hot object. Only after he failed to explain the spectrum by classical means did he resort to the quantum, assigning a characteristic energy to light that depends on the frequency. At high frequencies, the heat energy available to produce light is less than one “quantum” of light, which cuts off the light emitted at those frequencies, rescuing the model from the “ultraviolet catastrophe” that afflicted classical approaches to the problem.
Planck used this quantum idea as a desperate trick, but Einstein picked it up and ran with us, arguing that the quantum hypothesis Planck resorted to from desperation could explain another phenomenon, the photoelectric effect. Einstein’s simple “heuristic” works brilliantly, and was what officially won him the Nobel Prize. Niels Bohr took these quantum ideas and applied them to atoms, making the first model that could begin to explain the absorption and emission of light by atoms, which used discrete energy states for electrons within atoms, and light with a characteristic energy proportional to the frequency. And quantum physics was off and running.
This history is useful because it grounds an exceptionally weird subject in concrete solutions to concrete problems. Nobody woke up one morning and asserted the existence of particles that behave like waves and vice versa. Instead, physicists were led to the idea, somewhat reluctantly but inevitably, by rigorously working out the implications of specific experiments. Going through the history makes the weird end result more plausible, and gives future physicists something to hold on to as they start on the journey for themselves.
This historical approach also has educational benefits when applied to the other great pillar of “modern physics” classes, namely Einstein’s theory of special relativity. This is another subject that is often introduced in very abstract ways– envisioning a universe filled with clocks and meter sticks and pondering the meaning of simultaneity, or considering the geometry of spacetime. Again, there are good things to take away from this– I learned some great stuff from Takeuchi’s Illustrated Guide to Relativity and Cox and Forshaw’s Why Does E=mc2?. But for a lot of students, the abstraction of this approach leads to them thinking “Why in hell are we talking about this nonsense?”
Some of those concerns can be addressed by a historical approach. The most standard way of doing this is to go back to the Michelson-Morley experiment, started while Einstein was in diapers, that proved that the speed of light was constant. But more than that, I think it’s useful to bring in some actual history– I’ve found it helpful to draw on Peer Galison’s argument in Einstein’s Clocks, Poincare’s Maps.
Galison notes that the abstract concerns about simultaneity that connect to relativity arise very directly from considering very concrete problems of timekeeping and telegraphy, used in surveying the planet to determine longitude, and establishing the modern system of time zones to straighten out the chaos that multiple incompatible local times created for railroads.
Poincare was deeply involved in work on longitude and timekeeping, and these practical issues led him to think very philosophically about the nature of time and simultaneity, several years before Einstein’s relativity. Einstein, too, was in an environment where practical timekeeping issues would’ve come up with some regularity, which naturally leads to similar thoughts. And it wasn’t only those two– Hendrik Lorentz and George FitzGerald worked out much of the necessary mathematics for relativity on their own.
So, adding some history to discussions of relativity helps both ground what is otherwise a very abstract process and also helps reinforce a broader understanding of science as a process. Relativity, seen through a historical perspective, is not merely the work of a lone genius who was bored by his job in the patent office, but the culmination of a process involving many people thinking about issues of practical importance.
Bringing in some history can also have benefits when discussing topics that are modern enough to be newsworthy. There’s a big argument going on at the moment about dark matter, with tempers running a little high. On the one hand, some physicists question whether it’s time to consider alternative explanations, while other observations bolster the theory.
Dark matter is a topic that might very well find its way into classroom discussions, and it’s worth introducing a bit of the history to explore this. Specifically, it’s good to go back to the initial observations of galaxy rotation curves. The spectral lines emitted by stars and hot gas are redshifted by the overall motion of the galaxy, but also bent into a sort of S-shape by the fact that stars on one side tend to be moving toward us due to the galaxy’s rotation, and stars on the other side tend to be moving away. The difference between these lets you find the velocity of rotation as a function of distance from the center of the galaxy, and this turns out to be higher than can be explained by the mass we can see and the normal behavior of gravity.
This work is worth introducing not only because these galaxy rotations are the crux of the matter for the current argument, but because they help make an important point about science in context. The initial evidence for something funny about these rotation curves came largely from work by Vera Rubin, who was a remarkable person. As a woman in a male-dominated field, she had to overcome many barriers along the course of her career.
Bringing up the history of dark matter observations is a natural means to discuss science in a broader social context, and the issues that Rubin faced and overcame, and how those resonate today. Talking about her work and history allows both a better grounding for the current dark matter fights, and also a chance to make clear that science takes place within and is affected by a larger societal context. That’s probably at least as important an issue to drive home as any particular aspect of the dark matter debate.
So, those are some examples of areas in which a historical approach to physics is actively helpful to students, not just a way to delay the teaching of more modern topics. By grounding abstract issues in concrete problems, making the collaborative and cumulative nature of science clear, and placing scientific discoveries in a broader social context, adding a bit of history to the classroom helps students get a better grasp on specific physics topics, and also on science as a whole.
About the author: Chad Orzel is Associate Professor in the Department of Physics and Astronomy at Union College
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This website is educational. Materials within it are being used in accord with the Fair Use doctrine, as defined by United States law.
§107. Limitations on Exclusive Rights: Fair Use. Notwithstanding the provisions of section 106, the fair use of a copyrighted work, including such use by reproduction in copies or phone records or by any other means specified by that section, for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research, is not an infringement of copyright. In determining whether the use made of a work in any particular case is a fair use, the factors to be considered shall include: the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes; the nature of the copyrighted work; the amount and substantiality of the portion used in relation to the copyrighted work as a whole; and the effect of the use upon the potential market for or value of the copyrighted work. (added pub. l 94-553, Title I, 101, Oct 19, 1976, 90 Stat 2546)
Ulugh Beg
There’s a new docudrama coming out about the life of Ulugh Beg, a medieval astronomer who made Samarkand, now Uzbekistan, a thriving center of culture and science in the 15th century.
Intro adapted from Wikipedia
Mīrzā Muhammad Tāraghay bin Shāhrukh (Chagatay: میرزا محمد طارق بن شاہ رخ, Persian: میرزا محمد تراغای بن شاہ رخ), better known as Ulugh Beg (الغ بیگ) (1394- 1449), was a Timurid ruler as well as an astronomer, mathematician and sultan.
His commonly known name is a moniker, translated as “Great Ruler”
Ulugh Beg was notable for his work in astronomy-related mathematics, such as trigonometry and spherical geometry.
He built the great Ulugh Beg Observatory in Samarkand between 1424 and 1429. It is considered to have been one of the finest observatories in the Islamic world at the time. He built the Ulugh Beg Madrasah (1417–1420) in Samarkand and Bukhara, transforming the cities into cultural centers of learning in Central Asia.
He ruled Uzbekistan, Tajikistan, Turkmenistan, Kyrgyzstan, southern Kazakhstan and most of Afghanistan from 1411 to 1449.
The following is from Gizmodo, The Trailer for The Man Who Unlocked the Universe Is a Gorgeous Mixture of Science and Action, by George Dvorsky
A full 150 years before Galileo gazed at the heavens with his telescope, Ulugh Beg (1394-1449) was building some of the largest astronomical instruments on Earth. Incredibly, he used his observatory to map the stars and create charts that are still considered highly accurate, even by today’s standards.
Beg managed to measure the duration of the year to within 25 seconds of the actual figure, and he even correctly calculated the Earth’s axial tilt at 23.52 degrees. In addition to astronomy, he was a capable mathematician and biologist. He was also a Timurid ruler, transforming the cities of Samarkand and Bukhara into vibrant cultural centers.
A new 38-minute docudrama, titled Ulugh Beg: The Man Who Unlocked the Universe and directed by Bakhodir Yuldashev (Shima, Angel of Death), chronicles the life of the little-known scientist, from his birth as a prince through to his unconventional childhood and eduction, and ending with his untimely death.
Actor Armand Assante (Gotti, American Gangster) portrays Beg, and Vincent Cassel (Black Swan, Shrek) provides the narration. It features some neat CGI, live-action re-enactments of historical events, and interviews with academics and astronauts.
The film will be available for rent or purchase on Amazon starting Friday, June 22.
Stone walls
Walk into a patch of forest in New England, and chances are you will—almost literally—stumble across a stone wall. According to Robert Thorson, a landscape geologist at University of Connecticut, these walls are “damn near everywhere” in the forests of rural New England.
Carlisle stone wall Massachusetts at 42° 30′ 21.79″ N, 71° 21′ 15.83″ from Wikimedia
Jeanna Bryner, in Livescience, writes about the rediscovery of the lost archaeological landscape of New England.
Leaf-off (left) and Leaf-on (right) aerial photographs with a modern road superimposed through the northeast corner of the image for reference .
These stone walls and other archaeological features could not be seen with traditional aerial photographs shown here. This figure illustrates the advantage of LiDAR data with a point spacing of 1 meter or better over traditional map views of the landscape for archaeological purposes.
Examinations of airborne scans, using light detection and ranging (LiDAR), of three New England towns have revealed networks of old stone walls, building foundations, old roads, dams and other features, many of which long were forgotten. Here, stone walls are yellow, abandoned roads are red, and building foundations are outlined by green squares.
LiDAR is not only a powerful tool on its own; it can also be used in conjunction with the many types of historical documents available to those performing research in this geographic area,” Johnson and Ouimet write in the Journal of Archaeological Science.
As an example, this 1934 aerial photograph taken of an area in Preston, Conn., shows a farmstead — cleared fields, forest, stone walls or fences, a house, a barn and other outbuildings, and a road running through the farm.
Now compare with this aerial image from 2012.
from Livescience, Images: ‘Lost’ New England Archaeology Sites Revealed in LiDAR Photos, 1/16/14
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New England Is Crisscrossed With Thousands of Miles of Stone Walls
That’s enough to circle the globe—four times.
By Anna Kusmer 5/4/18
Walk into a patch of forest in New England, and chances are you will—almost literally—stumble across a stone wall. Thigh-high, perhaps, it is cobbled together with stones of various shapes and sizes, with splotches of lichen and spongy moss instead of mortar. Most of the stones are what are called “two-handers”—light enough to lift, but not with just one hand. The wall winds down a hill and out of sight. According to Robert Thorson, a landscape geologist at University of Connecticut, these walls are “damn near everywhere” in the forests of rural New England.
He estimates that there are more than 100,000 miles of old, disused stone walls out there, or enough to circle the globe four times.
Who would build a stone wall, let alone hundreds of thousands of miles of them, in the middle of the forest? No one. The walls weren’t built in the forest but in and around farms. By the middle of the 19th century, New England was over 70 percent deforested by settlers, a rolling landscape of smallholdings as far as the eye could see. But by the end of the century, industrialization and large-scale farms led to thousands of fields being abandoned, to begin a slow process of reforestation.
“New England had great pastures,” says Thorson. “It was a beef-butter-bacon economy.”
As farmers cleared those New England forests, they found rocks—lots and lots of them. The glaciers that receded at the end of the last Ice Age left behind millions of tons of stone in a range of sizes. New England soils remain notoriously stony today.
When life gives you stones? Build a wall. Farmers pulled these plow-impeding stones from their fields and piled them on the edges. “The farmer’s main interest was his fields,” says Thorson. “The walls are simply a disposal pile. It was routine farm work.” This process was replicated at thousands of farms across the region—a collective act of labor on a glacial scale.
The supply of stone seemed endless. A field would be cleared in the autumn, and there would be a whole new crop of stones in the spring. This is due to a process known as “frost heave.” As deforested soils freeze and thaw, stones shift and migrate to the surface. “People in the Northeast thought that the devil had put them there,” says Susan Allport, author of the book Sermons in Stone: The Stone Walls of New England and New York. “They just kept coming.”
Wall-building peaked in the mid-1800s when, Thorson estimates, there were around 240,000 miles of them in New England. That amounts to roughly 400 million tons of stone, or enough to build the Great Pyramid of Giza—more than 60 times over.
No one dedicates more time to thinking about these walls than Thorson, who has written a children’s book, a field guide, and countless articles about them since he first moved to New England in 1984. Thorson, bald and bearded, a mossy stone himself, is a landscape geologist, and he distinctly remembers his first walks in the New England woods—and coming across one stone wall after another. His mind was full of questions about what they were and who built them, “it was a phenomenon that was extraordinary,” he says. “One thing led to another, and I got obsessed on the topic”.
Thorson started the Stone Wall Initiative in 2002, aimed at educating the public about this distinctive feature of their forests, in addition to conserving the walls and studying how they impact the landscape around them. Thorson has built a reputation as the ultimate expert on this phenomenon. “You know how a natural history museum would have a person who identifies stuff for you? I’m kind of that guy for stone walls,” he says.
Every year he takes his students to a maple-beech forest stand in Storrs, Connecticut, which he calls “The Glen,” to look at a classic farmstead stone wall. This wall is thigh-high, and mostly built of gneiss and schist, metamorphic rocks common in the valley flanks of central New England. With Thorson’s help, one begins to see a little structure in how the stones were stacked—in messy tiers, by a farmer who added one load at a time.
Thorson may be particularly obsessed with the walls, but he’s not alone in the interest. He is constantly invited to speak at garden clubs, historical societies, public libraries, and more. “The interest doesn’t die down,” he says. “Twenty years later, it’s still going on.”
His field guide, Exploring Stone Walls, is a directory of some of the most unusual, interesting, or distinctive walls in the region. The tallest example is a mortared sea wall beneath the Cliff Walk in Newport, Rhode Island, measuring over 100 feet. The oldest wall, in Popham Point, Maine, dates to 1607. Thorson’s favorite historically significant wall is at the Old Manse, a historic home in Concord, Massachusetts. It provided cover for minutemen firing on the British during the Revolutionary War. Thorson also highlights Robert Frost’s “Mending Wall,” located on his farm in Derry, New Hampshire, the inspiration for the famous line, “Good fences make good neighbors.”
Thorson knows about as much as one can know about the world-wonder- scale web of walls across the Northeast, but there remains much to learn, particularly in terms of what they mean for ecosystems, such as their role as both habitat and impediment to wildlife, and their effect on erosion and sedimentation. “It sounds silly,” he says, “but we almost know nothing about them.”
Geographer and landscape archaeologist Katharine Johnson earned her doctorate mapping stone walls from above, using lidar (light detection and ranging) technology. Lidar is similar to radar, only instead of using radio waves to detect objects, it uses light. Laser pulses—thousands per second—are emitted from a specially equipped plane. There are so many of these pulses, that some are able to hit the small spaces between leaves and penetrate all the way to the forest floor, even through thick tree cover. Johnson’s lidar images reveal the exent of those crisscrossing stone walls in a way nothing else can.
Her research shows that, stripped of the region’s resurgent forests, the walls provide a snapshot of 19th-century history—a map of what land was cleared and farmed at the time. Combined with other data on the forests themselves, this can help specialists model historic forest cover and, in turn, help ecologists understand how forests grow back after they have been disturbed or cleared entirely. The walls can hold the key to New England’s social history, including settlement patterns and farming styles. They provide a static backdrop against which change can be measured.
“Stone walls are the most important artifacts in rural New England,” Thorson says. “They’re a visceral connection to the past. They are just as surely a remnant of a former civilization as a ruin in the Amazon rain forest.”
Each of the millions of stones that make up New England stone walls was held by a person, usually a subsistence farmer, or perhaps a hired Native American or a slave. What remains is a trace of countless individual acts etched on the landscape. “Those labors,” says Allport, “hundreds of years later, they endure.”
source atlasobscura.com/articles/new-england-stone-walls
Related references
https://www.livescience.com/42638-lost-new-england-archaeology-lidar-photos.html
https://news.nationalgeographic.com/news/2014/01/140103-new-england-archaeology-lidar-science/
Scientific articles
Rediscovering the lost archaeological landscape of southern New England using airborne light detection and ranging (LiDAR), Katharine M.Johnson and William B.Ouimet, Journal of Archaeological Science, Volume 43, March 2014, Pages 9-20
This website is educational. Materials within it are being used in accord with the Fair Use doctrine, as defined by United States law.
§107. Limitations on Exclusive Rights: Fair Use. Notwithstanding the provisions of section 106, the fair use of a copyrighted work, including such use by reproduction in copies or phone records or by any other means specified by that section, for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research, is not an infringement of copyright. In determining whether the use made of a work in any particular case is a fair use, the factors to be considered shall include: the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes; the nature of the copyrighted work; the amount and substantiality of the portion used in relation to the copyrighted work as a whole; and the effect of the use upon the potential market for or value of the copyrighted work. (added pub. l 94-553, Title I, 101, Oct 19, 1976, 90 Stat 2546)
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Learning Standards
Massachusetts History and Social Science Curriculum Framework
HISTORY AND GEOGRAPHY
1. Use map and globe skills learned in prekindergarten to grade five to interpret different
kinds of projections, as well as topographic, landform, political, population, and climate
maps. (G)
2. Use geographic terms correctly, such as delta, glacier, location, settlement, region,
natural resource, human resource, mountain, hill, plain, plateau, river, island, isthmus,
peninsula, erosion, climate, drought, monsoon, hurricane, ocean and wind currents,
tropics, rain forest, tundra, desert, continent, region, country, nation, and urbanization.
(G)
3. Interpret geographic information from a graph or chart and construct a graph or chart
that conveys geographic information (e.g., about rainfall, temperature, or population
size data). (G)
Lectures on the history of physics
Galileo and Einstein: Lectures on the history of physics
Michael Fowler – University of Virginia Physics
Binnacle
Our school is right by Boston Harbor – learning about the sea is second nature to many of our staff. So we love to tie maritime history and science into our curriculum.
Photo by RK
As you enter our school, you pass by a binnacle – what was it used for?
A binnacle is a waist-high case, found on the deck of a ship, that holds the compass.
It is mounted in gimbals to keep it level while the ship pitched and rolled.
It also has a mechanism to compensate for errors in detecting the Earth’s magnetic field.
Every ship’s captain would use one, for navigating in and out of Boston Harbor, and around the world.
Here we see Boston Harbor – now let’s get in to how the binnacle works!
This map is from mass.gov/eea/images/dcr
Why did we need to develop the binnacle?
Excerpted from Magnetic Deviation: Comprehension, Compensation and Computation by Ron Doerfler
Today, radio navigational systems such as LORAN and GPS, and inertial navigation systems with ring and fiber-optic gyros, gyrocompasses and the like have reduced the use of a ship’s compass to worst-case scenarios. But this triumph of mathematics and physics over the mysteries of magnetic deviation, entered into at a time when magnetic forces were barely understood and set against the backdrop of hundreds of shipwrecks and thousands of lost lives, is an enriching chapter in the history of science.
The Sources of Compass Error
Ron Doerfler writes:
Compasses on ships fail to point to true (geographic) north due to two factors:
Magnetic variation (or magnetic declination) – the angle between magnetic north and geographic north due to the local direction of the Earth’s magnetic field, and
Magnetic deviation – the angle between the compass needle and magnetic north due to the presence of iron within the ship itself.
The algebraic sum of the magnetic variation and the magnetic deviation is known as the compass error. It is a very important thing to know.
Magnetic Variation
Magnetic variation has been known from voyages since the early 1400s at least. Certainly Columbus was distressed as he crossed the Atlantic to find that magnetic north and true north (from celestial sightings) drifted significantly…
We now know that the locations of the Earth’s magnetic poles are not coincident with the geographic poles—not even close, really—and they are always wandering around.
Image from commons.wikimedia.org, Magnetic_North_Pole_Positions. Red circles mark magnetic north pole positions as determined by direct observation, blue circles mark positions modelled using the GUFM model (1590–1980) and the IGRF model (1980–2010) in 2 year increments.
What’s the difference between where a compass needle points (magnetic north) and the geographic north pole? This is called the declination It’s smallest near the equator, but generally gets large as one moves towards the poles.
On this map, the green arrows – the direction from the compass – point towards the magnetic north. The red arrows point towards the geographical north pole.
Notice how the left location (in Pacific ocean) shows the compass point a bit east of where we’d hope it would point; in the right location (in Atlantic Ocean) it shows the compass point a bit west of where we’d hope it points.
There’s also a special line where the magnetic north and geographic north point in the same direction.
Image from Drillingformulas.com by Rachain J i
Here we can see how many degrees of deviation there are – the # of degrees between where the compass points, and where the north pole is. But – wait for it – the image is changing? The magnetic fields are significantly changing every year!
from USGS.gov, faqs, what is declination
Magnetic Deviation
Ron Doerfler writes
There is an additional effect on the compass needle that took much longer to appreciate and even longer to understand. This magnetic deviation is due to the iron in a ship…
The first notice in print of this effect was by Joao de Castro of Portugal in 1538, in which he identified “the proximity of artillery pieces, anchors and other iron” as the source.
As better compass designs appeared, a difference in compass readings with their placement on the same ship became more apparent. Captains John Smith and James Cook warned about iron nails in the compass box or iron in steerage, and on Cook’s second circumnavigation William Wales found that changes in the ship’s course changed their measurements of magnetic variation by as much as 7°.
Here we see a modern naval vessel, with it’s own magnetic field. As a metal ship moves through Earth’s magnetic field, an electric current is produced within all that metal – and that current produces it’s own magnetic field. This field can affect the ship’s compass. That’s why a binnacle is designed to be adjustable, to compensate for this field. – RK
image from slideplayer.com/slide/1632522/
Ron Doerfler writes
Captain Matthew Flinders (1774-1815) spent years in the very early 1800s on voyages to investigate these effects…. [he] eventually discovered that an iron bar placed vertically near the compass helped overcome the magnetic deviation. This Flinder’s bar is still used today in ships’ binnacles.
Apps & Interactives
NOAA Historical Magnetic Declination
Activities
Hands-on Activity: Nautical Navigation. Teachengineering.org
https://oceanservice.noaa.gov/education/lessons/plot_course.html
https://asa.com/certifications/asa-105-coastal-navigation/
Educational opportunities and museums
http://www.capecodmaritimemuseum.org/education/
http://abycinc.org/?page=standards
Important components
Quadrantal spheres (spherical quadrantal correctors)
Hood, over the compass bowl
flinders bar (vertical, soft iron corrector)
Learning Standards
Ocean Literacy Scope and Sequence for Grades K-12
6. The ocean and humans are inextricably interconnected: From the ocean we get foods, medicines, and mineral and energy resources. In addition, it provides jobs, supports our nation’s economy, serves as a highway for transportation of goods and people, and plays a role in national security.
Massachusetts 2016 Science and Technology/Engineering (STE) Standards
7.MS-PS2-5. Use scientific evidence to argue that fields exist between objects with mass, between magnetic objects, and between electrically charged objects that exert force on each other even though the objects are not in contact.
HS-PS2-1. Analyze data to support the claim that Newton’s second law of motion is a mathematical model describing change in motion (the acceleration) of objects when acted on by a net force….{forces can include magnetic forces}
HS-PS3-5. Develop and use a model of magnetic or electric fields to illustrate the forces and changes in energy between two magnetically or electrically charged objects changing relative position in a magnetic or electric field, respectively.
History standards
National Standards for History Basic Edition, 1996
5-12 Identify major technological developments in shipbuilding, navigation, and naval warfare and trace the cultural origins of various innovations.
Massachusetts History and Social Science Curriculum Framework
The Political, Intellectual and Economic Growth of the Colonies. Explain the importance of maritime commerce in the development of the economy of colonial Massachusetts, using historical societies and museums as needed.
National Curriculum Standards for Social Studies: A Framework for Teaching, Learning, and Assessment, National Council for the Social Studies, 2010.
Americapox
DNA evidence offers proof of North American native population decline due to arrival of Europeans
by Bob Yirka, Phys.org
Most history books report that Native American populations in North America declined significantly after European colonizers appeared, subsequent to the “discovery” of the new world by Christopher Columbus in 1492, reducing their numbers by half or more in some cases. Most attribute this decline in population to the introduction of new diseases, primarily smallpox and warfare.
To back up such claims, historians have relied on archaeological evidence and written documents by new world settlers. Up to now however, no physical evidence has been available to nail down specifics regarding population declines, such as when they actually occurred and what caused it to occur. Now however, three researchers with various backgrounds in anthropological and genome sciences have banded together to undertake a study based on mitochondrial DNA evidence, and have found, as they report in their study published in the Proceedings of the National Academy of Sciences, that native populations in North America did indeed decline by roughly fifty percent, some five hundred years ago.
What’s perhaps most interesting in the study, is the implication that the sudden drop in population appeared to occur almost right after the arrival of Europeans, which means before settlement began. This means that the decline would have come about almost exclusively as a result of disease sweeping naturally through native communities, rather than from warfare, or mass slaughter as some have suggested and that stories of settlers using smallpox as a weapon may be exaggerated.
Also of interest is that the researchers found that the native population peaked some 5,000 years ago, and held steady, or even declined slightly, until the arrival of Europeans, and that the population decline that occurred was transient, meaning that it gradually rebounded as those Native Americans that survived the initial wave of smallpox passed on their hearty genes to the next generation.
The results of this research also seem to settle the argument of whether the massive loss of life due to disease was regional, as some historians have argued, or widespread as others have claimed; siding firmly with the latter.
In studying the DNA, of both pre-European arrival native population samples and that of their ancestors alive today, the researchers noted that those alive today are more genetically similar to one another than were their ancestors, which suggests a population decline and then resurgence, and that is how, by backtracking, they came to conclude that the decline occurred half a century ago. The authors are quick to point out however that the margin of error in their work does allow for the possibility that the population decline occurred somewhat later than their results showed and note that further research will need to be done to create a more precise timeline of events.
Native Americans experienced a strong population bottleneck coincident with European contact, Brendan D. O’Fallona and Lars Fehren-Schmitz
PNAS, Published online before print December 5, 2011, doi: 10.1073/pnas.1112563108
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Americapox: The Missing Plague
By CGP Grey, an an educational YouTuber. He produces explanatory videos on science, politics, geography, economics, and history. This is a transcript of his video Americapox: The Missing Plague, www.cgpgrey.com/blog/americapox
Between the first modern Europeans arriving in 1492 and the Victorian age, the indigenous population of the new world [native American Indians] dropped by at least 90%.
The cause?
Not the conquistadores and company — they killed lots of people but their death count is nothing compared to what they brought with them: small pox, typhus, tuberculosis, influenza, bubonic plague, cholera, mumps, measles and more leapt from those first explores to the costal tribes, then onward the microscopic invaders spread through a hemisphere of people with no defenses against them. Tens of millions died.
These germs decided the fate of these battles long before the fighting started.
Now ask yourself: why didn’t Europeans get sick?
If new-worlders were vulnerable to old-world diseases, then surely old-worlders would be vulnerable to new world diseases.
Yet, there was no Americapox spreading eastward infecting Europe and cutting the population from 90 million to 9. Had Americapox existed it would have rather dampened European ability for transatlantic expansion.
To answer why this didn’t happen: we need first to distinguish regular diseases — like the common cold — from what we’ll call plagues.
1) Spread quickly between people.
Sneezes spread plages faster than handshakes which are faster than… closeness. Plagues use more of this than this.
2) They kill you quickly or you become immune.
Catch a plague and your dead within seven to thirty days. Survive and you’ll never get it again. Your body has learned to fight it, you might still carry it — the plague lives in you, you can still spread it, but it can’t hurt you.
The surface answer to this question isn’t that Europeans had better immune systems to fight off new world plages — it’s that new world didn’t have plagues for them to catch. They had regular diseases but there was no Americapox to carry.
These are history’s biggest killers, and they all come from the old world.
But why?
Let’s dig deeper, and talk Cholera, a plague that spreads if your civilization does a bad job of separating drinking water from pooping water. London was terrible at this making it the cholera capital of the world. Cholera can rip through dense neighborhoods killing swaths of the population, before moving onward. But that’s the key: it has to move on.
In a small, isolated group, a plague like cholera cannot survive — it kills all available victims, leaving only the immune and then theres nowhere to go — it’s a fire that burns through its fuel.
But a city — shining city on the hill — to which rural migrants flock, where hundreds of babies are born a day: this is sanctuary for the fire of plague; fresh kindling comes to it. The plague flares and smolders and flares and smolders again — impossible to extinguish.
Historically in city borders plagues killed faster than people could breed. Cities grew because more people moved to them than died inside of them. Cities only started growing from their own population in the 1900s when medicine finally left its leaches and bloodletting phase and entered its soap and soup phase — giving humans some tools to slow death.
But before that a city was an unintentional playground for plages and a grim machine to sort the immune from the rest.
So the deeper, answer is that The New World didn’t have plagues because the new world didn’t have big, dense, terribly sanitized deeply interconnected cities for plages to thrive.
OK, but The New World wasn’t completely barren of cities. And tribes weren’t completely isolated, otherwise the newly-arrived smallpox in the 1400s couldn’t have spread.
Cities are only part of the puzzle: they’re required for plages, but cities don’t make the germs that start the plagues — those germs come from the missing piece.
Now, most germs don’t want to kill you for the same reason you don’t want to burn down your house: germs live in you. Chromic diseases like leprosy are terrible because they’re very good at not killing you.
Plague lethality is an accident, a misunderstanding, because the germs that cause them don’t know they’re in humans, they’re germs that think they’re in this.
Plagues come from animals.
Whooping cough comes from pigs, and does flu as well as from birds. Our friend the cow alone is responsible for measles, tuberculosis, and smallpox.
For the cow these diseases are no big deal — like colds for us. But when cow germs get in humans thing things they do to make the cow a little sick, makes humans very sick. Deadly sick.
Germs jumping species like this is extraordinarily rare. That’s why generations of humans can spend time around animals just fine. Being the patient zero of a new animal-to-human plague is winning a terrible lottery.
But a colonial-age city raises the odds: there used to be animals everywhere, horses, herds of livestock in the streets, open slaughterhouses, meat markets pre-refrigeration, and a river of literal human and animal excrement running through it all.
A more perfect environment for diseases to jump species could hardly be imagined.
So the deeper answer is that plagues come from animals, but so rarely you have to raise the odds and with many chances for infection and give the new-born plague a fertile environment to grow. The old world had the necessary pieces in abundance.
But, why was a city like London filled with sheep and pigs and cows and Tenochtitlan wasn’t?
This brings us to the final level. (For this video anyway)
Some animals can be put to human use — this is what domestication means, animals you can breed, not just hunt.
Forget a the moment the modern world: go back to 10,000BC when tribes of humans reached just about everywhere. If you were in one of these tribes what local animals could you capture, alive, and successfully pen to breed?
Maybe you’re in North Dakota and thinking about catching a Buffalo: an unpredictable, violent tank on hooves, that can outrun you across the planes, leap over your head head and travels in herds thousands strong.
Oh, and you have no horses to help you — because there are no horses on the continent. Horses live here — and won’t be brought over until, too late.
It’s just you, a couple buddies, and stone-based tools. American Indians didn’t fail to domesticate buffalo because they couldn’t figure it out. They failed because it’s a buffalo. No one could do it — buffalo would have been amazing creature to put to human work back in BC, but it’s not going to happen — humans have only barely domesticated buffalo with all our modern tools.
The New World didn’t have good animal candidates for domestication. Almost everything big enough to be useful is also was to too dangerous, or too agile.
Meanwhile the fertile crescent to central Europe had: cows and and pigs and sheep and goats, easy pests animals comparatively begging to be domesticated.
A wild boar is something to contend with if you only have stone tools but it’s possible to catch and pen and bread and feed to eat — because pigs can’t leap to the sky or crush all resistance beneath their hooves.
In The New World the only native domestication contestant was: llamas. They’re better than nothing, which is probably why the biggest cities existed in South America — but they’re no cow. Ever try to manage a heard of llamas in the mountains of Peru? Yeah, you can do it, but it’s not fun. Nothing but drama, these llamas.
These might seem, cherry-picked examples, because aren’t there hundreds of thousands of species of animals? Yes, but when you’re stuck at the bottom of the tech tree almost none of them can be domesticated. From the dawn of man until this fateful meeting humans domesticated maybe a baker’s dozen of unique species the world over, and even to get that high a number you need to stretch it to include honeybees and silkworms. Nice to have, but you can’t build a civilization on a foundation of honey alone.
These early tribes weren’t smarter, or better at domestication. The old world had more valuable and easy animals. With dogs, herding sheep and cattle is easier. Now humans have a buddy to keep an eye on the clothing factory, and the milk and cheeseburger machine, and the plow-puller. Now farming is easier, which means there’s more benefit to staying put, which means more domestication, which means more food which means more people and more density and oh look where we’re going. Citiesville, population lots, bring your animals, plagues welcome.
That is the full answer: The lack of new world animals to domesticate, limited not only exposure to germs sources but also limited food production, which limited population growth, which limited cities, which made plagues in The New World an almost impossibility. In the old, exactly the reverse. And thus a continent full of plague and a continent devoid of it.
So when ships landed in the new world there was no Americapox to bring back.
The game of civilization has nothing to do with the players, and everything to do with the map. Access to domesticated animals in numbers and diversity, is the key resource to bootstrapping a complex society from nothing — and that complexity brings with it, unintentionally, a passive biological weaponry devastating to outsiders.
Start the game again but move the domesticable animals across the sea and history’s arrow of disease and death flows in the opposite direction.
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Don’t Blame Columbus for All the Indians’ Ills
By JOHN NOBLE WILFORD, OCT. 29, 2002, The New York Times
Europeans first came to the Western Hemisphere armed with guns, the cross and, unknowingly, pathogens. Against the alien agents of disease, the indigenous people never had a chance. Their immune systems were unprepared to fight smallpox and measles, malaria and yellow fever.
The epidemics that resulted have been well documented. What had not been clearly recognized until now, though, is that the general health of Native Americans had apparently been deteriorating for centuries before 1492.
That is the conclusion of a team of anthropologists, economists and paleopathologists who have completed a wide-ranging study of the health of people living in the Western Hemisphere in the last 7,000 years.
The researchers, whose work is regarded as the most comprehensive yet, say their findings in no way diminish the dreadful impact Old World diseases had on the people of the New World. But it suggests that the New World was hardly a healthful Eden.
More than 12,500 skeletons from 65 sites in North and South America — slightly more than half of them from pre-Columbians — were analyzed for evidence of infections, malnutrition and other health problems in various social and geographical settings.
The researchers used standardized criteria to rate the incidence and degree of these health factors by time and geography. Some trends leapt out from the resulting index. The healthiest sites for Native Americans were typically the oldest sites, predating Columbus by more than 1,000 years. Then came a marked decline.
”Our research shows that health was on a downward trajectory long before Columbus arrived,” Dr. Richard H. Steckel and Dr. Jerome C. Rose, study leaders, wrote in ”The Backbone of History: Health and Nutrition in the Western Hemisphere,” a book they edited. It was published in August.
Dr. Steckel, an economist and anthropologist at Ohio State University, and Dr. Rose, an anthropologist at the University of Arkansas, stressed in interviews that their findings in no way mitigated the responsibility of Europeans as bearers of disease devastating to native societies. Yet the research, they said, should correct a widely held misperception that the New World was virtually free of disease before 1492.
In an epilogue to the book, Dr. Philip D. Curtin, an emeritus professor of history at Johns Hopkins University, said the skeletal evidence of the physical well-being of pre-Columbians ”shows conclusively that however much it may have deteriorated on contact with the outer world, it was far from paradisiacal before the Europeans and Africans arrived.”
About 50 scientists and scholars joined in the research and contributed chapters to the book. One of them, Dr. George J. Armelagos of Emory University, a pioneer in the field of paleopathology, said in an interview that the research provided an ”evolutionary history of disease in the New World.”
The surprise, Dr. Armelagos said, was not the evidence of many infectious diseases, but that the pre-Columbians were not better nourished and in general healthier.
Others said the research, supported by the National Science Foundation and Ohio State, would be the talk of scholarly seminars for years to come and the foundation for more detailed investigations of pre-Columbian health. Dr. Steckel is considering conducting a similar study of health patterns well into European prehistory.
”Although some of the authors occasionally appear to overstate the strength of the case they can make, they are also careful to indicate the limitations of the evidence,” Dr. Curtin wrote of the Steckel-Rose research. ”They recognize that skeletal material is the best comparative evidence we have for the human condition over such a long period of time, but it is not perfect.”
The research team gathered evidence on seven basic indicators of chronic physical conditions that can be detected in skeletons — namely, degenerative joint disease, dental health, stature, anemia, arrested tissue development, infections and trauma from injuries. Dr. Steckel and Dr. Rose called this ”by far the largest comparable data set of this type ever created.”
The researchers attributed the widespread decline in health in large part to the rise of agriculture and urban living. People in South and Central America began domesticating crops more than 5,000 years ago, and the rise of cities there began more than 2,000 years ago.
These were mixed blessings. Farming tended to limit the diversity of diets, and the congestion of towns and cities contributed to the rapid spread of disease. In the widening inequalities of urban societies, hard work on low-protein diets left most people vulnerable to illness and early death.
Similar signs of deleterious health effects have been found in the ancient Middle East, where agriculture started some 10,000 years ago. But the health consequences of farming and urbanism, Dr. Rose said, appeared to have been more abrupt in the New World.
The more mobile, less densely settled populations were usually the healthiest pre-Columbians. They were taller and had fewer signs of infectious lesions in their bones than residents of large settlements. Their diet was sufficiently rich and varied, the researchers said, for them to largely avoid the symptoms of childhood deprivation, like stunting and anemia. Even so, in the simplest hunter-gatherer societies, few people survived past age 50. In the healthiest cultures in the 1,000 years before Columbus, a life span of no more than 35 years might be usual.
In examining the skeletal evidence, paleopathologists rated the healthiest pre-Columbians to be people living 1,200 years ago on the coast of Brazil, where they had access to ample food from land and sea. Their relative isolation protected them from most infectious diseases.
Conditions also must have been salubrious along the coasts of South Carolina and Southern California, as well as among the farming and hunting societies in what is now the Midwest. Indian groups occupied the top 14 spots of the health index, and 11 of these sites predate the arrival of Europeans.
The least healthy people in the study were from the urban cultures of Mexico and Central America, notably where the Maya civilization flourished presumably at great cost to life and limb, and the Zuni of New Mexico. The Zuni lived at a 400-year-old site, Hawikku, a crowded, drought-prone farming pueblo that presumably met its demise before European settlers made contact.
It was their hard lot, Dr. Rose said, to be farmers ”on the boundaries of sustainable environments.”
”Pre-Columbian populations were among the healthiest and the least healthy in our sample,” Dr. Steckel and Dr. Rose said. ”While pre-Columbian natives may have lived in a disease environment substantially different from that in other parts of the globe, the original inhabitants also brought with them, or evolved with, enough pathogens to create chronic conditions of ill health under conditions of systematic agriculture and urban living.”
In recent examinations of 1,000-year-old Peruvian mummies, for example, paleopathologists discovered clear traces of tuberculosis in their lungs, more evidence that native Americans might already have been infected with some of the diseases that were thought to have been brought to the New World by European explorers.
Tuberculosis bears another message: as an opportunistic disease, it strikes when times are tough, often overwhelming the bodies of people already weakened by malnutrition, poor sanitation in urban centers and debilitated immune systems.
The Steckel-Rose research extended the survey to the health consequences of the first contacts with American Indians by Europeans and Africans and the health of European-Americans and African-Americans up to the early 20th century.
Not surprisingly, African-American slaves were near the bottom of the health index. An examination of plantation slaves buried in South Carolina, Dr. Steckel said, revealed that their poor health compared to that of ”pre-Columbian Indian populations threatened with extinction.”
On the other hand, blacks buried at Philadelphia’s African Church in the 1800’s were in the top half of the health index. Their general conditions were apparently superior to those of small-town, middle-class whites, Dr. Steckel said.
The researchers found one exception to the rule that the healthiest sites for Native Americans were the oldest sites. Equestrian nomads of the Great Plains of North America in the 19th century seemed to enjoy excellent health, near the top of the index. They were not fenced in to farms or cities.
In a concluding chapter of their book, Dr. Steckel and Dr. Rose said the study showed that ”the health decline was precipitous with the changes in ecological environments where people lived.” It is not a new idea in anthropology, they conceded, ”but scholars in general have yet to absorb it.”
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Related articles
The Great Dying 1616-1619, Ipswich Historical Commission
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Fair use
This website is educational. Materials within it are being used in accord with the Fair Use doctrine, as defined by United States law.
§107. Limitations on Exclusive Rights: Fair Use
Notwithstanding the provisions of section 106, the fair use of a copyrighted work, including such use by reproduction in copies or phone records or by any other means specified by that section, for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research, is not an infringement of copyright. In determining whether the use made of a work in any particular case is a fair use, the factors to be considered shall include:
the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes;
the nature of the copyrighted work;
the amount and substantiality of the portion used in relation to the copyrighted work as a whole; and
the effect of the use upon the potential market for or value of the copyrighted work. (added pub. l 94-553, Title I, 101, Oct 19, 1976, 90 Stat 2546)
How elections are impacted by a 100 million year old coastline
How elections are impacted by a 100 million year old coastline
Earth Science and Geology impact American social and political life in unexpected ways
Hale County in west central Alabama and Bamberg County in southern South Carolina are 450 miles apart. Both counties have a population of 16,000 of which around 60% are African American. The median households and per capita incomes are well below their respective state’s median, in Hale nearly $10,000 less. Both were named after confederate officers–Stephen Fowler Hale and Francis Marion Bamberg. And although Hale’s county seat is the self-proclaimed Catfish Capitol, pulling catfish out of the Edisto River in Bamberg County is a favorite past time.
These two counties share another unique feature. Amidst a blanket of Republican red both Hale and Bamberg voted primarily Democratic in the 2000, 2004, and again in the 2008 presidential elections. Indeed, Hale and Bamberg belong to a belt of counties cutting through the deep south–Mississippi, Alabama, Georgia, South Carolina, and North Carolina–that have voted over 50% Democratic in recent presidential elections.
Why? A 100 million year old coastline.
During the Cretaceous, 139-65 million years ago, shallow seas covered much of the southern United States. These tropical waters were productive–giving rise to tiny marine plankton with carbonate skeletons which overtime accumulated into massive chalk formations. The chalk, both alkaline and porous, lead to fertile and well-drained soils in a band, mirroring that ancient coastline and stretching across the now much drier South. This arc of rich and dark soils in Alabama has long been known as the Black Belt.
But many, including Booker T. Washington, coopted the term to refer to the entire Southern band. Washington wrote in his 1901 autobiography, Up from Slavery, “The term was first used to designate a part of the country which was distinguished by the color of the soil. The part of the country possessing this thick, dark, and naturally rich soil…”
Over time this rich soil produced an amazingly productive agricultural region, especially for cotton. In 1859 alone a harvest of over 4,000 cotton bales was not uncommon within the belt. And yet, just tens of miles north or south this harvest was rare. Of course this level of cotton production required extensive labor.
As Washington notes further in his autobiography, “The part of the country possessing this thick, dark, and naturally rich soil was, of course, the part of the South where the slaves were most profitable, and consequently they were taken there in the largest numbers. Later and especially since the war, the term seems to be used wholly in a political sense—that is, to designate the counties where the black people outnumber the white.”
The legacy of ancient coastlines, chalk, soil, cotton, and slavery can still be seen today. African Americans make up over 50%, in some cases over 85%, of the population in Black Belt counties. As expected this has and continues to deeply influence the culture of the Black Belt. J. Sullivan Gibson writing in 1941 on the geology of the Black Belt noted, “The long-conceded regional identity of the Black Belts roots no more deeply its physical fundament of rolling prairie soil than in its cultural, social, and economic individuality.” And so this plays out in politics.
This Black Belt with its predominantly African American population consistently votes overwhelmingly for Democratic candidates in presidential elections. The pattern is especially pronounced on maps when a Republican candidate has secured the presidency as Bush did in 2000 and 2004. In Southern states where a Republican secures the nomination, almost the entirety of Black Belt counties still lean Democratic. This leads to a Blue Belt of Democratic counties across the South. Even when Clinton, a Democrat, overwhelmingly took most Southern states, the percentages of those voting Democrat was still highest in the Black Belt counties.
But the Black Belt has not always been visible on maps during elections. The Voting Rights Act, outlawing discriminatory voting practices, was passed in 1965. As result, a year earlier in the 1964 elections larger numbers of African Americans were excluded from the polls in Southern states. And, in turn, the blue band we see today was not visible.
Long heralded as the Black Belt for rich dark soils and later for the rich African American culture and population, it may equally be referred to as the Blue Belt to reflect both its oceanic geology and the political leanings that resulted from it.
About the author: Craig McClain is the Executive Director of the Lousiana University Marine Consortium. He has conducted deep-sea research for 20 years and published over 50 papers in the area. He has participated in and led dozens of oceanographic expeditions taken him to the Antarctic and the most remote regions of the Pacific and Atlantic.
Deep Sea News: How presidential elections are impacted by a 100 million year old coastline
– – – – – – – – – – – – – – –
Now we move to further data, from the original article, Geology and Election 2000: Overview, by Steven Dutch, Natural and Applied Sciences,University of Wisconsin – Green Bay
On the map of electoral returns for the presidential election of 2000 is a feature instantly recognizable to a geologist: in the otherwise pro-Bush South, an arcuate band of pro-Gore counties sweeps from eastern Mississippi, across Alabama and Georgia and into the Carolinas.
My geologist’s eye was immediately drawn to this arc because it coincides almost exactly with a series of rock units on the Geologic Map of the United States. Why would election returns follow rock outcrops?
In the map below, Cretaceous rock units (139-65 million years old) are shown in shades of green. Older rock units are in gray, younger ones in yellow. The complex NE-trending patterns in Alabama, Georgia and South Carolina are deformed rocks of the Appalachians. In NW Alabama, the older rocks are flat-lying layers of the continental interior.
Comparison with the geologic maps shows that the arc actually consists of three segments.
- In Mississippi and Alabama the pro-Gore band of counties corresponds very closely with the units labeled uK – upper Cretaceous. We might suspect that the most likely explanation for this part of the arc has to do with economic patterns dictated by the soils. Most of the electoral and demographic patterns associated with the band end abruptly in NE Mississippi.
- In Georgia, the Cretaceous outcrop band is very narrow. It is surprising how clear the pro-Gore band is in Georgia considering how narrow and discontinuous the outcrop band of Cretaceous rocks is. This part of the arc may have less to do with the rocks themselves than the boundary between the Appalachians and the Coastal Plain.
- In South Carolina, however, the band of Democratic counties is well defined but is consistently seaward of the Cretaceous rock units. In fact, on some maps there seems to be a weak anti-correlation between the Cretaceous rocks in South Carolina and the political and demographic trends noted for the other three states. However, the South Carolina portion of the arc turns out to be consistent in election returns and a variety of other demographic factors.
This band shows up with varying degrees of prominence for previous elections as well. It shows the same correlation with rock units in Mississippi, Alabama and Georgia and the same lack of correlation in South Carolina. It further shows strong correlation with demographic trends.
The Coastal plain rocks slope gently seaward toward the Gulf and Atlantic coasts, a structure called a homocline. I therefore propose to call the arc of pro-Democratic counties, which is reflected in a variety of demographic trends, the Cretaceous Homoclinal Arc of Demography, which can be abbreviated by an acronym that more than anything else symbolizes the election of 2000: CHAD.
(more to come)
text
This website is educational. Materials within it are being used in accord with the Fair Use doctrine, as defined by United States law.
§107. Limitations on Exclusive Rights: Fair Use
Notwithstanding the provisions of section 106, the fair use of a copyrighted work, including such use by reproduction in copies or phone records or by any other means specified by that section, for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research, is not an infringement of copyright. In determining whether the use made of a work in any particular case is a fair use, the factors to be considered shall include:
the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes;
the nature of the copyrighted work;
the amount and substantiality of the portion used in relation to the copyrighted work as a whole; and
the effect of the use upon the potential market for or value of the copyrighted work. (added pub. l 94-553, Title I, 101, Oct 19, 1976, 90 Stat 2546)
Model ship building in Boston
Wooden ship models are scale representations of ships constructed mainly of wood. This type of model has been built for over two thousand years. Herein we see how math and scale conversion factors are used in building model ships.
First let’s look at some photos of a scale model of the HMS Victory. She is a 104-gun first-rate ship of the line of the Royal Navy, ordered in 1758, laid down in 1759 and launched in 1765. She is best known for her role as Lord Nelson’s flagship at the Battle of Trafalgar on 21 October 1805.
In 1922, HMC Victory was moved to a dry dock at Portsmouth, England, and preserved as a museum ship. She has been the flagship of the First Sea Lord since October 2012 and is the world’s oldest naval ship still in commission.
The artist: George Kaiser grew up on Boston Harbor. In addition to being an American soldier and later an engineer with a research think tank, he did ship modeling, often volunteering at the USS Constitution Museum.
In the USS Constitution Museum workshop, 1990’s.
Her we have a model of The US Navy Schooner Enterprise. The third ship to be named USS Enterprise was a schooner, built by Henry Spencer at Baltimore, Maryland, in 1799.
It was overhauled and rebuilt several times, effectively changing from a twelve-gun schooner to a fourteen-gun topsail schooner and eventually to a brig.
Front view
Here we have the Flying Fish
Donald McKay, one of the greatest designers of the time, built the Flying Fish in 1851 at East Boston, MA. Flying Fish was registered at the Boston Common House as a ship of 1505 tons, with a hull length of 207 feet, and a beam of 22 feet. She sailed from New York to San Francisco in 92 days–only 3 days short of the record set by her sister ship the Flying Cloud.
Her dimensions were 198’6″×38’2″×22′. The deadrise was 25″. She wrecked on the 23rd of November 1958 off Fuzhou, China en route to New York with a cargo of tea.
The Flying Fish
The last model ship hull that my father,ז״ל, was working on.
Scale conversion factors
Written by George Kaiser (His text was later incorporated into the Wikipedia article on model ships.)
Instead of using plans made specifically for models, many model shipwrights use the actual blueprints for the original vessel. One can take drawings for the original ship to a blueprint service and have them blown up, or reduced to bring them to the new scale.
For instance, if the drawings are in 1/4″ scale and you intend to build in 3/16″, tell the service to reduce them 25%. You can use the conversion table below to determine the percentage of change.
You can easily work directly from the original drawings however by changing scale each time you make a measurement.
| from | to 1/8 | to 3/16 | to 1/4 |
|---|---|---|---|
| 1/16 | 2.0 | 3.0 | 4.0 |
| 1/12 | 1.5 | 2.25 | 3.0 |
| 3/32 | 1.33 | 2.0 | 2.67 |
| 1/8 | 1.0 | 1.5 | 2.0 |
| 5/32 | 0.8 | 1.2 | 1.6 |
| 3/16 | 0.67 | 1.0 | 1.33 |
| 1.5 | 0.625 | 0.94 | 1.25 |
| 7/32 | 0.57 | 0.86 | 1.14 |
| 1/4 | 0.5 | 0.75 | 1.0 |
The equation for converting a measurement in one scale to that of another scale is D2 = D1 x F where:
-
D1 = Dimension in the “from-scale”
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D2 = Dimension in the “to-scale”
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F = Conversion factor between scales
Example:
A yardarm is 6″ long in 3/16″ scale.
Find its length in 1/8″ scale.
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F = .67 (from table)
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D2 = 6″ X .67 = 4.02 = 4″
It is easier to make measurements in the metric system and then multiply them by the scale conversion factor. Scales are expressed in fractional inches, but fractions themselves are harder to work with than metric measurements.
For example, a hatch measures 1″ wide on the draft. You are building in 3/16″ scale. Measuring the hatch in metric, you measure 25 mm.
The conversion factor for 1/4″ to 3/16′, according to the conversion table is .75. So 25 mm x .75 = 18.75 mm, or about 19 mm. That is the hatch size in 3/16″ scale.
Conversion is a fairly simple task once you start measuring in metric and converting according to the scale.
There is a simple conversion factor that allows you to determine the approximate size of a model by taking the actual measurements of the full-size ship and arriving at a scale factor. It is a rough way of deciding whether you want to build a model that is about two feet long, three feet long, or four feet long.
Here is a ship model conversion example using a real ship, the Hancock. This is a frigate appearing in Chappelle’s “History of American Sailing Ships”.
In this example we want to estimate its size as a model. We find that the length is given at 136 ft 7 in, which rounds off to 137 feet.
| 1/8 scale | Feet divided by 8 |
| 3/16 scale | Feet divided by 5.33 |
| 1/4 scale | Feet divided by 4 |
To convert feet (of the actual ship) to the number of inches long that the model will be, use the factors in the table on the right.
To find the principal dimensions (length, height, and width) of a (square rigged) model in 1/8″ scale, then:
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Find scaled length by dividing 137 by 8 = 17.125″
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Find 50% of 17.125 and add it to 17.125 (8.56 + 17.125 = 25.685, about 25.5)
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Typically, the height of this model will be its length less 10% or about 23.1/2″
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Typically, the beam of this model will be its length divided by 4, or about 6 1/2″
Although this technique allows you to judge the approximate length of a proposed model from its true footage, only square riggers will fit the approximate height and beam by the above factors.
To approximate these dimensions on other craft, scale the drawings from which you found the length and arrive at her mast heights and beam.
Reference: Williams, Guy R. The World of Model Ships and Boats London 1971 Page 30
Model of USS Constitution on display
My father’s masterpiece was a museum quality scale ship model of the USS Constitution. She is also known as Old Ironsides, a wooden-hulled, three-masted heavy frigate of the United States Navy. She is the world’s oldest commissioned naval vessel still afloat. She was launched in 1797, one of six original frigates authorized for construction by the Naval Act of 1794 and the third constructed.
She was built at Edmund Hartt’s shipyard in the North End of Boston, Massachusetts. Her first duties were to provide protection for American merchant shipping during the Quasi-War with France and to defeat the Barbary pirates in the First Barbary War.
Constitution is most noted for her actions during the War of 1812 against the United Kingdom, when she captured numerous merchant ships and defeated five British warships: HMS Guerriere, Java, Pictou, Cyane, and Levant. The battle with Guerriere earned her the nickname “Old Ironsides” and public adoration that has repeatedly saved her from scrapping.
(description here from Wikipedia)
Here’s my father at home working on the hull.
Here is a montage of the construction.
Here is a frontal shot of his finished model, now on permanent display at the USS Constitution Museum in Charlestown, Massachusetts.
Related subjects
How ships have navigated the seas – History, culture, and science
The Science and History of the Sea
Extreme weather and teachable moments in Boston Harbor
External links
The USS Constitution Model Shipwright Guild
We are the largest model ship association on the East Coast and our friendly meetings overlooking Old Ironsides at the USS Constitution Museum are well attended. Novices and experienced model builders alike can have fun developing resources, experiences, and skills by joining us.
The USS Constitution Museum serves as the memory and educational voice of USS Constitution, by collecting, preserving, and interpreting the stories of “Old Ironsides” and the people associated with her. Located in Boston, Charlestown Navy Yard, part of the Boston National Historical Park area.
A nonprofit educational organization with an international membership of historians, ship model makers, artists and laypersons with a common interest in the history, beauty and technical sophistication of ships and their models.
Model Ship World – by the NRG (Nautical Research Guild) – Discussion forums
Learning Standards
2016 Massachusetts Science and Technology/Engineering Curriculum Framework
Ocean Literacy The Essential Principles and Fundamental Concepts of Ocean Sciences: March 2013 and Ocean Literacy Network. The Centers for Ocean Sciences Education Excellence (COSEE) and Lawrence Hall of Science, University of California, Berkeley
Massachusetts History and Social Science Curriculum Frameworks
5.11 Explain the importance of maritime commerce in the development of the economy of colonial Massachusetts, using historical societies and museums as needed. (H, E)
5.32 Describe the causes of the war of 1812 and how events during the war contributed to a sense of American nationalism. A. British restrictions on trade and impressment. B. Major battles and events of the war, including the role of the USS Constitution, the burning of the Capitol and the White House, and the Battle of New Orleans.
National Council for the Social Studies: National Curriculum Standards for Social Studies
Time, Continuity and Change: Through the study of the past and its legacy, learners examine the institutions, values, and beliefs of people in the past, acquire skills in historical inquiry and interpretation, and gain an understanding of how important historical events and developments have shaped the modern world. This theme appears in courses in history, as well as in other social studies courses for which knowledge of the past is important.
A study of the War of 1812 enables students to understand the roots of our modern nation. It was this time period and struggle that propelled us from a struggling young collection of states to a unified player on the world stage. Out of the conflict the nation gained a number of symbols including USS Constitution. The victories she brought home lifted the morale of the entire nation and endure in our nation’s memory today. – USS Constitution Museum, National Education Standards
Common Core ELA: Reading Instructional Texts
CCSS.ELA-LITERACY.RI.9-10.1
Cite strong and thorough textual evidence to support analysis of what the text says explicitly as well as inferences drawn from the text.
CCSS.ELA-LITERACY.RI.9-10.4
Determine the meaning of words and phrases as they are used in a text, including figurative, connotative, and technical meanings
CCSS.ELA-LITERACY.W.9-10.1.C
Use words, phrases, and clauses to link the major sections of the text, create cohesion, and clarify the relationships between claim(s) and reasons, between reasons and evidence, and between claim(s) and counterclaims.
CCSS.ELA-LITERACY.W.9-10.1.D
Establish and maintain a formal style and objective tone while attending to the norms and conventions of the discipline in which they are writing.
CCSS.ELA-LITERACY.W.9-10.4
Produce clear and coherent writing in which the development, organization, and style are appropriate to task, purpose, and audience.
Carbon dating
Introduction
“At an archaeological dig, a piece of wooden tool is unearthed – and the archaeologist finds it to be 5,000 years old. A child mummy is found high in the Andes – and the archaeologist says the child lived more than 2,000 years ago. How do scientists know how old an object or human remains are? What methods do they use and how do these methods work?
Carbon-14 dating is a way of determining the age of archaeological artifacts of a biological origin up to about 50,000 years old. It is used in dating things such as bone, cloth, wood and plant fibers that were created in the relatively recent past by human activities.”
- How Stuff Works, How Carbon-14 Dating Works, Marshall Brain
“The method was developed by Willard Libby in the late 1940s and soon became a standard tool for archaeologists. Libby received the Nobel Prize in Chemistry for his work in 1960. ” – Wikipedia
How does it work?
Radiocarbon is constantly being created in the atmosphere by the interaction of cosmic rays with atmospheric nitrogen.
From the matthew2262 wordpress blog.
The resulting radiocarbon combines with atmospheric oxygen to form radioactive carbon dioxide.
That is incorporated into plants by photosynthesis.
Animals then acquire 14 C by eating the plants.
When the animal or plant dies, it stops exchanging carbon with its environment, and from that point onwards the amount of 14 C it contains begins to decrease, as the 14
C undergoes radioactive decay.
Measuring the amount of 14 C in a sample from a dead plant or animal such as a piece of wood or a fragment of bone provides information that can be used to calculate when the animal or plant died.
The older a sample is, the less 14 C there is to be detected, and because the half-life of 14 C (the period of time after which half of a given sample will have decayed) is about 5,730 years.
The oldest dates that can be reliably measured by this process date to around 50,000 years ago, although special preparation methods occasionally permit accurate analysis of older samples.
– Carbon Dating, Wikipedia
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As years go by, how much C14 is left?
C12 does not decay and remains constant in a sample, whereas C14 decays at an even, constant rate.
By measuring the ratio of C12 to C14, we can understand how long a sample has been around for.
The half life of C 14 is around 5,730 years. As seen by the second graph, this means that if a sample has half of the C14 it should usually have, it has been around for 5,730 years. A quarter of the amount, double that time, one eight of the original amount, more still.
Carbon dating is only as accurate as the consistency of it’s decay rate, which is unchanging and extremely uniform.
It is almost exclusively used for organic material as all life on earth is carbon based.
There is a misconception that carbon dating is used to date the age of the earth. For longer time scales, other elements are used, based on the same principles.
Graphs from a video by Scientific American that explains carbon dating. Watch the full video here How Does Radiocarbon Dating Work? – Instant Egghead #28: Scientific American
- text from http://blunt-science.tumblr.com/post/109954909373/a-representation-of-the-age-span-carbon-dating-is
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Is radiocarbon dating reliable?
Excerpted from National Center for Science Education, by Christopher Gregory Weber:
http://ncse.com/cej/3/2/answers-to-creationist-attacks-carbon-14-dating
Radiocarbon dating can easily establish that humans have been on the earth for over twenty thousand years …. it is one of the most reliable of all the radiometric dating methods.
Question: How does carbon-14 dating work?
Answer:
Cosmic rays in the upper atmosphere are constantly converting the isotope nitrogen-14 (N-14) into carbon-14 (C-14 or radiocarbon).
Living organisms are constantly incorporating this C-14 into their bodies along with other carbon isotopes.
When the organisms die, they stop incorporating new C-14
The old C-14 starts to decay back into N-14 by emitting beta particles.
The older an organism’s remains are, the less beta radiation it emits because its C-14 is steadily dwindling at a predictable rate.
So, if we measure the rate of beta decay in an organic sample, we can calculate how old the sample is. C-14 decays with a half-life of 5,730 years.
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Question: Kieth and Anderson radiocarbon-dated the shell of a living freshwater mussel and obtained an age of over two thousand years. ICR creationists claim that this discredits C-14 dating. How do you reply?
Answer: It does discredit the C-14 dating of freshwater mussels, but that’s about all. Kieth and Anderson show considerable evidence that the mussels acquired much of their carbon from the limestone of the waters they lived in and from some very old humus as well.
Carbon from these sources is very low in C-14 because these sources are so old and have not been mixed with fresh carbon from the air. Thus, a freshly killed mussel has far less C-14 than a freshly killed something else, which is why the C-14 dating method makes freshwater mussels seem older than they really are.
When dating wood there is no such problem because wood gets its carbon straight from the air, complete with a full dose of C-14.
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Question: A sample that is more than fifty thousand years old shouldn’t have any measurable C-14. Coal, oil, and natural gas are supposed to be millions of years old; yet creationists say that some of them contain measurable amounts of C-14, enough to give them C-14 ages in the tens of thousands of years. How do you explain this?
Answer: Very simply. Radiocarbon dating doesn’t work well on objects much older than twenty thousand years, because such objects have so little C-14 left that their beta radiation is swamped out by the background radiation of cosmic rays and potassium-40 (K-40) decay.
Younger objects can easily be dated, because they still emit plenty of beta radiation, enough to be measured after the background radiation has been subtracted out of the total beta radiation. However, in either case, the background beta radiation has to be compensated for, and, in the older objects, the amount of C-14 they have left is less than the margin of error in measuring background radiation. As Hurley points out:
Without rather special developmental work, it is not generally practicable to measure ages in excess of about twenty thousand years, because the radioactivity of the carbon becomes so slight that it is difficult to get an accurate measurement above background radiation. (p. 108)
Cosmic rays form beta radiation all the time; this is the radiation that turns N-14 to C-14 in the first place. K-40 decay also forms plenty of beta radiation. Stearns, Carroll, and Clark point out that “. . . this isotope [K-40] accounts for a large part of the normal background radiation that can be detected on the earth’s surface” (p. 84).
This radiation cannot be totally eliminated from the laboratory, so one could probably get a “radiocarbon” date of fifty thousand years from a pure carbon-free piece of tin. However, you now know why this fact doesn’t at all invalidate radiocarbon dates of objects younger than twenty thousand years and is certainly no evidence for the notion that coals and oils might be no older than fifty thousand years.
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Question: Creationists such as Cook (1966) claim that cosmic radiation is now forming C-14 in the atmosphere about one and one-third times faster than it is decaying. If we extrapolate backwards in time with the proper equations, we find that the earlier the historical period, the less C-14 the atmosphere had.
If we extrapolate as far back as ten thousand years ago, we find the atmosphere would not have had any C-14 in it at all. If they are right, this means all C-14 ages greater than two or three thousand years need to be lowered drastically and that the earth can be no older than ten thousand years. How do you reply?
Answer: Yes, Cook is right that C-14 is forming today faster than it’s decaying. However, the amount of C-14 has not been rising steadily as Cook maintains; instead, it has fluctuated up and down over the past ten thousand years. How do we know this? From radiocarbon dates taken from bristlecone pines. There are two ways of dating wood from bristlecone pines: one can count rings or one can radiocarbon-date the wood.
Since the tree ring counts have reliably dated some specimens of wood all the way back to 6200 BC, one can check out the C-14 dates against the tree-ring-count dates. Admittedly, this old wood comes from trees that have been dead for hundreds of years, but you don’t have to have an 8,200-year-old bristlecone pine tree alive today to validly determine that sort of date. It is easy to correlate the inner rings of a younger living tree with the outer rings of an older dead tree. The correlation is possible because, in the Southwest region of the United States, the widths of tree rings vary from year to year with the rainfall, and trees all over the Southwest have the same pattern of variations.
When experts compare the tree-ring dates with the C-14 dates, they find that radiocarbon ages before 1000 BC are really too young—not too old as Cook maintains. For example, pieces of wood that date at about 6200 BC by tree-ring counts date at only 5400 BC by regular C-14 dating and 3900 BC by Cook’s creationist revision of C-14 dating (as we see in the article, “Dating, Relative and Absolute,” in the Encyclopaedia Britannica). So, despite claims, C-14 before three thousand years ago was decaying faster than it was being formed and C-14 dating errs on the side of making objects from before 1000 BC look too young, not too old.
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Question: But don’t trees sometimes produce more than one growth ring per year? Wouldn’t that spoil the tree-ring count?
Answer: If anything, the tree-ring sequence suffers far more from missing rings than from double rings. This means that the tree-ring dates would be slightly too young, not too old.
Of course, some species of tree tend to produce two or more growth rings per year. But other species produce scarcely any extra rings. Most of the tree-ring sequence is based on the bristlecone pine. This tree rarely produces even a trace of an extra ring; on the contrary, a typical bristlecone pine has up to 5 percent of its rings missing. Concerning the sequence of rings derived from the bristlecone pine, Ferguson says:
In certain species of conifers, especially those at lower elevations or in southern latitudes, one season’s growth increment may be composed of two or more flushes of growth, each of which may strongly resemble an annual ring.
Such multiple growth rings are extremely rare in bristlecone pines, however, and they are especially infrequent at the elevation and latitude (37� 20′ N) of the sites being studied. In the growth-ring analyses of approximately one thousand trees in the White Mountains, we have, in fact, found no more than three or four occurrences of even incipient multiple growth layers. (p. 840)
In years of severe drought, a bristlecone pine may fail to grow a complete ring all the way around its perimeter; we may find the ring if we bore into the tree from one angle, but not from another. Hence at least some of the missing rings can be found. Even so, the missing rings are a far more serious problem than any double rings.
Other species of trees corroborate the work that Ferguson did with bristlecone pines. Before his work, the tree-ring sequence of the sequoias had been worked out back to 1250 BC. The archaeological ring sequence had been worked out back to 59 BC. The limber pine sequence had been worked out back to 25 BC.
The radiocarbon dates and tree-ring dates of these other trees agree with those Ferguson got from the bristlecone pine. But even if he had had no other trees with which to work except the bristlecone pines, that evidence alone would have allowed him to determine the tree-ring chronology back to 6200 BC. …
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Question: Does outside archaeological evidence confirm the C-14 dating method?
Answer: Yes. When we know the age of a sample through archaeology or historical sources, the C-14 method (as corrected by bristlecone pines) agrees with the age within the known margin of error.
For instance, Egyptian artifacts can be dated both historically and by radiocarbon, and the results agree. At first, archaeologists used to complain that the C-14 method must be wrong, because it conflicted with well-established archaeological dates; but, as Renfrew has detailed, the archaeological dates were often based on false assumptions.
One such assumption was that the megalith builders of western Europe learned the idea of megaliths from the Near-Eastern civilizations. As a result, archaeologists believed that the Western megalith-building cultures had to be younger than the Near Eastern civilizations.
Many archaeologists were skeptical when Ferguson’s calibration with bristlecone pines was first published, because, according to his method, radiocarbon dates of the Western megaliths showed them to be much older than their Near-Eastern counterparts.
However, as Renfrew demonstrated, the similarities between these Eastern and Western cultures are so superficial that the megalith builders of western Europe invented the idea of megaliths independently of the Near East. So, in the end, external evidence reconciles with and often confirms even controversial C-14 dates.
One of the most striking examples of different dating methods confirming each other is Stonehenge. C-14 dates show that Stonehenge was gradually built over the period from 1900 BC to 1500 BC, long before the Druids, who claimed Stonehenge as their creation, came to England.
Astronomer Gerald S. Hawkins calculated with a computer what the heavens were like back in the second millennium BC, accounting for the precession of the equinoxes, and found that Stonehenge had many significant alignments with various extreme positions of the sun and moon (for example, the hellstone marked the point where the sun rose on the first day of summer). Stonehenge fits the heavens as they were almost four thousand years ago, not as they are today, thereby cross-verifying the C-14 dates.
Textbooks
Relative Ages of Rocks: WIkiBooks
(WikiBooks: A project hosted by the Wikimedia Foundation for the creation of free content textbooks)
http://en.wikibooks.org/wiki/High_School_Earth_Science/Relative_Ages_of_Rocks
http://en.wikibooks.org/wiki/High_School_Earth_Science/Absolute_Ages_of_Rocks
External links
Willard Libby and Radiocarbon Dating. American Chemical Society
Learning Standards
A Framework for K-12 Science Education: Practices, Crosscutting Concepts, and Core Ideas (2012), from the National Research Council of the National Academies.
By the end of grade 12. Radioactive decay lifetimes and isotopic content in rocks provide a way of dating rock formations and thereby fixing the scale of geological time.
College Board Standards for College Success: Science
ES.3 Earth’s History: Relative and Absolute dating. Students understand that various dating methods — relative and absolute — have been used to determine the age of Earth.
Suggested Connections. Between Earth Science and Other Disciplines: Evidence of Common Ancestry and Divergence (LS.1.1); Living Systems and the Physical Environment (LS.3.1); Nuclear Chemistry (C.1.6); Nuclear Interactions and the Conservation of Mass–Energy (P.2.3)
Benchmarks: American Association for the Advancement of Science.
Knowledge of radioactivity helps them understand how rocks can be dated, which helps them appreciate the scale of geologic time… Scientific evidence indicates that some rock layers are several billion years old. 4C/H6** (BSL)
Michelangelo’s Secret Message in the Sistine Chapel
Michelangelo’s Secret Message in the Sistine Chapel: A Juxtaposition of God and the Human Brain
Scientific American, R. Douglas Fields on May 27, 2010
At the age of 17 he began dissecting corpses from the church graveyard. Between the years 1508 and 1512 he painted the ceiling of the Sistine Chapel in Rome. Michelangelo Buonarroti—known by his first name the world over as the singular artistic genius, sculptor and architect—was also an anatomist, a secret he concealed by destroying almost all of his anatomical sketches and notes. Now, 500 years after he drew them, his hidden anatomical illustrations have been found—painted on the ceiling of the Sistine Chapel, cleverly concealed from the eyes of Pope Julius II and countless religious worshipers, historians, and art lovers for centuries—inside the body of God.
This is the conclusion of Ian Suk and Rafael Tamargo, in their paper in the May 2010 issue of the scientific journal Neurosurgery. Suk and Tamargo are experts in neuroanatomy at the Johns Hopkins University School of Medicine in Baltimore, Maryland.
In 1990, physician Frank Meshberger published a paper in the Journal of the American Medical Association deciphering Michelangelo’s imagery with the stunning recognition that the depiction in God Creating Adam in the central panel on the ceiling was a perfect anatomical illustration of the human brain in cross section. Meshberger speculates that Michelangelo surrounded God with a shroud representing the human brain to suggest that God was endowing Adam not only with life, but also with supreme human intelligence.
Now in another panel The Separation of Light from Darkness, Suk and Tamargo have found more. Leading up the center of God’s chest and forming his throat, the researchers have found a precise depiction of the human spinal cord and brain stem.
Is the ceiling of the Sistine Chapel a 500 year-old puzzle that is only now beginning to be solved? What was Michelangelo saying by construction the voice box of God out of the brain stem of man? Is it a sacrilege or homage?
It took Michelangelo four years to complete the ceiling of the Sistine Chapel. He proceeded from east to west, starting from the entrance of the Chapel to finish above the altar. The last panel he painted depicts God separating light from darkness. This is where the researchers report that Michelangelo hid the human brain stem, eyes and optic nerve of man inside the figure of God directly above the altar.
Art critics and historians have long puzzled over the odd anatomical irregularities in Michelangelo’s depiction of God’s neck in this panel, and by the discordant lighting in the region. The figures in the fresco are illuminated diagonally from the lower left, but God’s neck, highlighted as if in a spotlight, is illuminated straight-on and slightly from the right.
How does one reconcile such clumsiness by the world’s master of human anatomy and skilled portrayer of light with bungling the image of God above the altar? Suk and Tamargo propose that the hideous goiter-disfigured neck of God is not a mistake, but rather a hidden message. They argue that nowhere else in any of the other figures did Michelangelo foul up his anatomically correct rendering of the human neck.
They show that if one superimposes a detail of God’s odd lumpy neck in the Separation of Light and Darkness on a photograph of the human brain as seen from below, the lines of God’s neck trace precisely the features of the human brain [see images at right].
There is something else odd about this picture. A role of fabric extends up the center of God’s robe in a peculiar manner. The clothing is bunched up here as is seen nowhere else, and the fold clashes with what would be the natural drape of fabric over God’s torso. In fact, they observe, it is the human spinal cord, ascending to the brain stem in God’s neck. At God’s waist, the robe twists again in a peculiar crumpled manner, revealing the optic nerves from two eyes, precisely as Leonardo Da Vinci had shown them in his illustration of 1487. Da Vinci and Michelangelo were contemporaries and acquainted with each other’s work.
The mystery is whether these neuroanatomical features are hidden messages or whether the Sistine Chapel a Rorshach tests upon which anyone can extract an image that is meaningful to themselves. The authors of the paper are, after all, neuroanatomists. The neuroanatomy they see on the ceiling may be nothing more than the man on the moon.
But Michelangelo also depicted other anatomical features elsewhere in the ceiling, according to other scholars; notably the kidney, which was familiar to Michelangelo and was of special interest to him as he suffered from kidney stones.
If the hidden figures are intentional, what do they mean? The authors resist speculation, but a great artist does not merely reproduce an object in a work of art, he or she evokes meaning through symbolism. Is Separation of Light from Darkness an artistic comment on the enduring clash between science and religion?
Recall that this was the age when the monk Copernicus was denounced by the Church for theorizing that the Earth revolved around the sun. It was a period of struggle between scientific observation and the authority of the Church, and a time of intense conflict between Protestants and Catholics.
It is no secret that Michelangelo’s relationship with the Catholic Church became strained. The artist was a simple man, but he grew to detest the opulence and corruption of the Church. In two places in the masterpiece, Michelangelo left self portraits—both of them depicting himself in torture. He gave his own face to Saint Bartholomew’s body martyred by being skinned alive, and to the severed head of Holofernes, who was seduced and beheaded by Judith.
Michelangelo was a devout person, but later in life he developed a belief in Spiritualism, for which he was condemned by Pope Paul IV. The fundamental tenet of Spiritualism is that the path to God can be found not exclusively through the Church, but through direct communication with God. Pope Paul IV interpreted Michelangelo’s Last Judgment, painted on the wall of the Sistine Chapel 20 years after completing the ceiling, as defaming the church by suggesting that Jesus and those around him communicated with God directly without need of Church. He suspended Michelangelo’s pension and had fig leaves painted over the nudes in the fresco. According to the artist’s wishes, Michelangelo’s body is not buried on the grounds of the Vatican, but is instead interred in a tomb in Florence.
Perhaps the meaning in the Sistine Chapel is not of God giving intelligence to Adam, but rather that intelligence and observation and the bodily organ that makes them possible lead without the necessity of Church directly to God. The material is rich for speculation and the new findings will doubtlessly spark endless interpretation. We may never know the truth, but in Separation of Light from Darkness, Michelangelo’s masterpiece combines the worlds of art, religion, science, and faith in a provocative and awe inspiring work of art, which may also be a mirror.
Images from “Concealed Neuroanatomy in Michelangelo’s Separation of Light From Darkness in the Sistine Chapel,” by Ian Suk and Rafael J. Tamargo in Neurosurgery, Vol. 66, No. 5, pp. 851-861.
About the author: R. Douglas Fields, Ph.D., is a neuroscientist and an adjunct professor at the University of Maryland, College Park. He is author of Why We Snap, about the neuroscience of sudden aggression, and The Other Brain, about glia. Fields serves on Scientific American Mind’s board of advisers.
Related articles
Separation of Light from Darkness. Article on the painting from Wikipedia.
KaiserScience 