KaiserScience

Home » history

Category Archives: history

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

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

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%.

Native_American_Population Plague

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.

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

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.”

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

Related articles

The Great Dying 1616-1619, Ipswich Historical Commission

_______________________

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)

Advertisements

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.

Creteaceous North America 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…”

Cretaceous rocks Alabama

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.

Cotton in 1859 USA

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.”

Slaves 1860 American south

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.

Census 2000 black percent African American

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.

Election Results 1964

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.

Election results 2000

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.

Cretaceous rocks Alabama

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

(this will be a work-in-progress)

Wooden ship models or wooden model ships are scale representations of ships, constructed mainly of wood. This type of model has been built for over two thousand years.

Introduction

HMS Victory

Dad's Kaiser HMS Victory model ship

ttt

Dad's Kaiser HMS Victory model ship II July 2004.JPG

US Navy Schooner Enterprise

Dad's Navy Schooner Enterprise model ship

ttt

Dad's Navy Schooner Enterprise II

ttt

Dad's Flying Fish ship model

The Flying Fish

ttt

Dad's Flying Fish ship model II

The last model ship hull that my father,ז״ל, was working on, before he passed away.

Dad's last model ship hull

ttt

Scale conversion factors

Written by George Kaiser (and later incorporated into Wikipedia)

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.

Table of Scale Conversion Factors
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”
  • D2 = Dimension in the “to-scale”
  • F = Conversion factor between scales

Example: A yardarm is 6″ long in 3/16″ scale. Find its length in 1/8″ scale.

  • F = .67 (from table)
  • 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:

  1. Find scaled length by dividing 137 by 8 = 17.125″
  2. Find 50% of 17.125 and add it to 17.125 (8.56 + 17.125 = 25.685, about 25.5)
  3. Typically, the height of this model will be its length less 10% or about 23.1/2″
  4. 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

 

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. In addition to our monthly meetings the Guild takes part in the annual meeting of model clubs from Connecticut, Massachusetts, New York, New Jersey, and Pennsylvania. We also attend the annual Salem Maritime Festival and the Antique & Classic Boat Festival, as well as the biennial Woods Hole Model Boat Show. Novices and experienced model builders alike can have fun developing resources, experiences, and skills by joining us.

The USS Constitution Museum, located in the Charlestown Navy Yard, which is part of the Boston National Historical Park

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.  Only yards away from “Old Ironsides,” the Museum is a “must see” for everyone visiting Boston, where interactive galleries take adults, families and children of all ages on a 200-year voyage.

The science and history of the sea

https://en.wikipedia.org/wiki/Ship_model

https://en.wikipedia.org/wiki/Wooden_ship_model

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

Common Core ELA Writing

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.

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.

Michelangelo Light Darkness First_Day_of_Creation

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.

Michelangelo 1

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.

Michelangelo 2

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.

https://blogs.scientificamerican.com/guest-blog/michelangelos-secret-message-in-the-sistine-chapel-a-juxtaposition-of-god-and-the-human-brain/

Related articles

Separation of Light from Darkness. Article on the painting from Wikipedia.

 

The Science and History of the Sea

 

Session 1: TBA at the USS Constitution Museum. Museum staff led.

Introductory movie (10 minutes)

  • Design your own frigate based on the templates of Constitution’s ship designer Joshua Humphreys: Students will produce drawings.
  • Made in America – what materials were used to create the USS Constitution? Students will create a list of 5 materials from the New England region.
  • Which of these woods is the hardest? Through dropping balls into difference woods, we can study the difference in how the ball bounces back. The kinetic energy of the rebounding ball is related to the amount of energy absorbed by the wood. Students will review with the teacher the difference between kinetic energy and potential energy.
  • Test your ship against other frigates in this hands-on challenge. Choose between three different types of ships for the ultimate test of size, speed and power: Students use this interactive computer simulation.
  • What’s so great about copper? Learn about the metals used in construction
  • Build a ship: Assemble 2D pieces into a 3D model – how quickly can they accurately complete the task?
  • Construction and launch: View this video, and then explain how a ship is safely launched from a drydock into the ocean.  Students will demonstrate that they understand the procedure by writing a step-by-step paragraph explaining the sequence.
  • How can a ship sail against the wind? Through a hands on experiment, see how changing the angle of the sail affects the motion of the boat: Students should be able to explain in complete sentences how the same wind can make a ship move forwards or backwards.
  • On the 2nd story of the museum, operate a working block-and-tackle system. This uses a classic simple machine. It is a system of two or more pulleys with a rope or cable threaded between them, usually used to lift or pull heavy loads. Back in the school building, we’ll review each of the classic simple machines.

On the 2nd story of the museum, operate a working block-and-tackle system. This uses a classic simple machine. It is a system of two or more pulleys with a rope or cable threaded between them, usually used to lift or pull heavy loads.

pulley simple machine

Session 2: TBA at the USS Constitution Museum. Museum staff led.

Details TBA.

Session 3: USS Constitution Visitor Center, Building 5 (teacher led)

10 minute orientation video

Can you locate where our school is on the 3D Boston Naval Shipyard model?

As students tour the visitor center, they practice ELA reading and writing skills (listed below) by briefly summarizing something they learn from each of these sections: They are encouraged to create drawings/tracings as they see fit to help illustrate their text.

  • Describe how ropes are made from string in the ropewalk
  • From wood & sail to steel & steam
  • Preparing for new technology
  • The shipyard in the Civil War
  • Ships and shipbuilding
  • The Navy Yard 1890-1974
  • Chain Forge and Foundary
  • The Navy Yard during World Wars I and II
  • Shipyard workers 1890 to 1974
  • The shipyard during the Cold War era 1945-1974

Session 4: Teaching math using the USS Constitition

Teaching math: Lessons from the USS Constitution

This teaching supplement contains math lessons organized in grade-level order. However, because many of the math skills used in these lessons are taught in multiple grades, both grade-level and lesson content are listed below.

Pre K–K 
Estimating Numbers of Objects

Grade 1
Estimating and Comparing Numbers of Objects

Grade 2
Estimating and Comparing Length, Width and Perimeter

Grade 3
Computing Time and Creating a Schedule

Grade 4
Drawing Conclusions from Data Sets

Grade 5
Creating and Interpreting Graphs from Tables

Grade 6
Range, Mean, Median and Mode and Stem-and-Leaf Plots

Grade 7
Converting Between Systems of Measurement

Grade 8
Calculating Volume

Algebra I (Grade 9–10)
Describing Distance and Velocity Graphs

Algebra I (Grade 9–10)
Writing Linear Equations

Algebra II (Grade 9–12)
Using Projectile Motion to Explore Maximums and Zeros

Precalculus & Advanced Math (Grade 10–12)
Using Parabolic Equations & Vectors to Describe the Path of Projectile Motion

Learning Standards

MA 2006 Science Curriculum Framework

2. Engineering Design. Central Concept: Engineering design requires creative thinking and consideration of a variety of ideas to solve practical problems. Identify tools and simple machines used for a specific purpose, e.g., ramp, wheel, pulley, lever.

Massachusetts Science and Technology/Engineering Curriculum Framework

HS-ETS4-5(MA). Explain how a machine converts energy, through mechanical means, to do work. Collect and analyze data to determine the efficiency of simple and complex machines.

Benchmarks, American Association for the Advancement of Science

In the 1700s, most manufacturing was still done in homes or small shops, using small, handmade machines that were powered by muscle, wind, or moving water. 10J/E1** (BSL)

In the 1800s, new machinery and steam engines to drive them made it possible to manufacture goods in factories, using fuels as a source of energy. In the factory system, workers, materials, and energy could be brought together efficiently. 10J/M1*

The invention of the steam engine was at the center of the Industrial Revolution. It converted the chemical energy stored in wood and coal into motion energy. The steam engine was widely used to solve the urgent problem of pumping water out of coal mines. As improved by James Watt, Scottish inventor and mechanical engineer, it was soon used to move coal; drive manufacturing machinery; and power locomotives, ships, and even the first automobiles. 10J/M2*

The Industrial Revolution developed in Great Britain because that country made practical use of science, had access by sea to world resources and markets, and had people who were willing to work in factories. 10J/H1*

The Industrial Revolution increased the productivity of each worker, but it also increased child labor and unhealthy working conditions, and it gradually destroyed the craft tradition. The economic imbalances of the Industrial Revolution led to a growing conflict between factory owners and workers and contributed to the main political ideologies of the 20th century. 10J/H2

Today, changes in technology continue to affect patterns of work and bring with them economic and social consequences. 10J/H3*

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

Common Core ELA Writing

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.

External links

The USS Constitution Museum, located in the Charlestown Navy Yard, which is part of the Boston National Historical Park

Aristotle’s laws of motion

Aristotle (Ἀριστοτέλης) 384–322 BCE was a Greek philosopher and scientist born in the city of Stagira, in classical Greece.

Aristotle bust

At 17 years of age, he joined Plato’s Academy in Athens and remained there until the age of thirty-seven (c. 347 BCE)

ancient-athens-map

His writings cover many subjects – including physics, biology, zoology, logic, ethics, poetry, theater, music, linguistics, and politics. They constitute the first comprehensive system of Western philosophy.

Shortly after Plato died, Aristotle left Athens and, at the request of Philip of Macedon, tutored Alexander the Great beginning in 343 BC.

Aristotle’s views on physical science profoundly shaped medieval scholarship. Their influence extended from Late Antiquity and the Early Middle Ages into the Renaissance, and were not replaced systematically until the Enlightenment and theories such as classical mechanics.

  • excerpted and adapted from Aristotle. (2016, October 20). Wikipedia, The Free Encyclopedia.

___________________________

Aristotle’s laws of motion

Aristotle bust
Aristotle set out 3 laws of motion, based on observations (but not on experiment)

* objects fall at a constant rate, that depends on their size and weight.

* there is a difference between “violent motion” versus “natural motion”

* objects in the heavens (the celestial sphere) move in circular motion,
without any external force compelling them to do so.
objects on Earth (the terrestrial sphere) move in straight lines,
unless forced to move in a circular motion.

Here is the modern, correct view of how gravity accelerates objects of different masses. (Does the mass and size affect the speed at which they fall?)

Yet here is Aristotle’s view of how gravity accelerates objects of different masses. (How does this differ from the previous animation?)

Aristotles view of gravity

What about pushing and pulling?

Natural vs Unnatural Motion

For objects on Earth, Aristotle thought that objects moved by people (“unnatural motion”) would move in a straight line, and when that “unnatural force” ran out, then natural motion would take over.

So what would happen if a canon fired a cannonball? Aristotle supposed that it would move in a straight line (due to the unnatural force), and then would fall straight down (due to a different, natural force.)

aristotle-idea-of-cannonball-not-projectile-motion

For Aristotle, once “violent motion” (from people) extinguished itself, natural motion takes over, and then the cannon ball falls to its natural place, the earth.

An animation of what this would look like.

However, as Galielo showed in the 1500’s, Aristotle’s view isn’t correct at all.  Anyone who watches an archer fire an arrow into the air, and carefully observes, would see that this doesn’t happen.

Galileo showed that the vertical motion (up/down) and horizontal motion (size-to-side) are independent.

When you fire an arrow, cannonball, or pop-fly in baseball, into the air, what happens?

The vertical motion slowly decreases, reaches zero (at the peak), and then increases in the opposite (downward) direction.

The horizontal motion actually stays constant (doesn’t speed up, or slow down.)

projectile-motion-canon-on-cliff

Heavenly forces vs terrestrial forces

Aristotle thought that heavenly (celestial) objects, by their nature, forever moved in circles – without any external force acting on them.

Earthly (terrestrial) objects were believed to have a separate set of laws of motion. Earthly objects supposedly would always stop moving, of their own accord, on their own.

As we will learn, there aren’t really 2 sets of laws (heavenly and earthly); rather, the laws of nature are the same everywhere:

* objects naturally travel only in straight lines.
* for objects to have a circular motion requires some external force,
keeping them pulled into a circular path

How could one of the greatest thinkers of the classical world be in error?
The ancient Greeks had a preference for attempting to find truth
through logic alone. Greeks viewed observations of the physical world
as a valid way  to learn, but held this to be inferior to intellect.

Also, Aristotle never ran experiments, so he was very limited in
what he could observe.
In the medieval era, Galileo (and others) ran controlled experiments.
The results of these experiments were analyzed with math.

Their findings ended the acceptance of Aristotelian physics.

Galileo learned critical thinking skills from his father, Vincenzo

Galileo and Einstein: History of Physics – Prof Michael Fowler

Vincenzo Galilei, father of Galileo.

Vincenzo Galilei, father of Galileo.

Galileo continued his father’s tradition of critical inquiry

Galileo rolled balls along surfaces tilted at different angles.

a. When ball rolls downward, it moves with Earth’s gravity, and its speed increases.

b. When ball rolls upward, it moves against gravity and loses speed.

c. When ball rolls on level plane, it doesn’t move with or against gravity.

 Galileo rolls balls slope

a. The ball rolls down the incline, and then up the opposite incline,
and reaches its initial height.

b. As the angle of the upward incline is reduced,
the ball rolls a greater distance before reaching its initial height.

c. If there is no friction, then the ball will never stop – unless it hits something.

Galileo rolls balls no friction never stops

Galileo’s conclusion was supported by another line of reasoning.

He described two inclined planes facing each other, as in Figure 3.4.
A ball released to roll down one plane would roll up the other to reach nearly the same height.
The smoother the planes were, the more nearly equal would be the initial and final heights.
He noted that the ball tended to attain the same height,
even when the second plane was longer,
and inclined at a smaller angle than the first plane.
Always, the ball went farther and tended to reach the same height.

Inclined Plane – Galileo’s Battle for the Heavens PBS NOVA

Video clip: Galileo’s inclined plane PBS media

Advanced: Similar studies with the moment of inertia

Rolling balls, cylinders and tubes down inclined plane: Moment of Inertia

http://makeagif.com/i/sWbNgM

 

Something special: The brachistochrone – curve of quickest descent. And the tautochrone- the curve for which the time taken by an object sliding without friction in uniform gravity to its lowest point is independent of its starting point.

brachistochrone-and-tautochrone-curve

____________________________

Aristotle’s laws of motion.

Excerpted from a lecture by Professor Michael Fowler, U. Va. Physics, 9/3/2008

http://galileoandeinstein.physics.virginia.edu/lectures/aristot2.html

What Aristotle achieved in those years in Athens was to begin a school of organized scientific inquiry on a scale far exceeding anything that had gone before. He first clearly defined what was scientific knowledge, and why it should be sought. In other words, he single-handedly invented science as the collective, organized enterprise it is today. Plato’s Academy had the equivalent of a university mathematics department, Aristotle had the first science department, truly excellent in biology, but, as we shall see, a little weak in physics.

After Aristotle, there was no comparable professional science enterprise for over 2,000 years, and his work was of such quality that it was accepted by all, and had long been a part of the official orthodoxy of the Christian Church 2,000 years later. This was unfortunate, because when Galileo questioned some of the assertions concerning simple physics, he quickly found himself in serious trouble with the Church.
Aristotle’s method of investigation:

defining the subject matter

considering the difficulties involved, by reviewing the generally accepted views on the subject, and suggestions of earlier writers

presenting his own arguments and solutions

This is the pattern modern research papers follow, Aristotle was laying down the standard professional approach to scientific research.

Aristotle often refuted an opposing argument by showing that it led to an absurd conclusion, this is called reductio ad absurdum (reducing something to absurdity). As we shall see later, Galileo used exactly this kind of argument against Aristotle himself, to the great annoyance of Aristotelians [people who fully agreed with Aristotle] 2,000 years after Aristotle.

[Aristotle himself likely would not have minded later thinkers disagreeing with him; in his lifetime Aristotle would change his mind, if he found new information or a more logical argument.]

In contrast to Plato, who felt the only worthwhile science to be the contemplation of abstract forms, Aristotle practiced detailed observation and dissection of plants and animals, to try to understand how each fitted into the grand scheme of nature, and the importance of the different organs of animals.

It is essential to realize that the world Aristotle saw around him in everyday life was very different indeed from that we see today. Every modern child has since birth seen cars and planes moving around, and soon finds out that these things are not alive, like people and animals. In contrast, most of the motion seen in fourth century Greece was people, animals and birds, all very much alive. This motion all had a purpose, the animal was moving to someplace it would rather be, for some reason, so the motion was directed by the animal’s will.

For Aristotle, this motion was therefore fulfilling the “nature” of the animal, just as its natural growth fulfilled the nature of the animal.

To account for motion of things obviously not alive, such as a stone dropped from the hand, Aristotle extended the concept of the “nature” of something to inanimate matter. He suggested that the motion of such inanimate objects could be understood by postulating that elements tend to seek their natural place in the order of things:

So earth moves downwards most strongly,
water flows downwards too, but not so strongly, since a stone will fall through water.
In contrast, air moves up (bubbles in water),
and fire goes upwards most strongly of all, since it shoots upward through air.

This general theory of how elements move has to be elaborated, of course, when applied to real materials, which are mixtures of elements. He would conclude that wood has both earth and air in it, since it does not sink in water.

Natural Motion and Violent Motion

Things also move because they are pushed. A stone’s natural tendency, if left alone and unsupported, is to fall, but we can lift it, or even throw it through the air.

Aristotle termed such forced motion “violent” motion as opposed to natural motion.

The term “violent” just means that some external force is applied to it.

Aristotle was the first to think quantitatively about the speeds involved in these movements. He made two quantitative assertions about how things fall (natural motion):

Heavier things fall faster, the speed being proportional to the weight.

The speed of fall of a given object depends inversely on the density of the medium it is falling through.

So, for example, the same body will fall twice as fast through a medium of half the density.

Notice that these rules have a certain elegance, an appealing quantitative simplicity. And, if you drop a stone and a piece of paper, it’s clear that the heavier thing does fall faster, and a stone falling through water is definitely slowed down by the water, so the rules at first appear plausible.

The surprising thing is, in view of Aristotle’s painstaking observations of so many things, he didn’t check out these rules in any serious way.

It would not have taken long to find out if half a brick fell at half the speed of a whole brick, for example. Obviously, this was not something he considered important.

From the second assertion above, he concluded that a vacuum cannot exist, because if it did, since it has zero density, all bodies would fall through it at infinite speed which is clearly nonsense.

For violent motion, Aristotle stated that the speed of the moving object was in direct proportion to the applied force.

This means first that if you stop pushing, the object stops moving.

This certainly sounds like a reasonable rule for, say,
pushing a box of books across a carpet, or an ox dragging a plough through a field.

(This intuitively appealing picture, however, fails to take account of
the large frictional force between the box and the carpet.
If you put the box on a sled and pushed it across ice,
it wouldn’t stop when you stop pushing.
Centuries later, Galileo realized the importance of friction in these situations.)

Learning Standards

2016 Massachusetts Science and Technology/Engineering Curriculum Framework
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.

HS-PS2-10(MA). Use free-body force diagrams, algebraic expressions, and Newton’s laws of motion to predict changes to velocity and acceleration for an object moving in one dimension in various situations

Massachusetts History and Social Science Curriculum Framework

The roots of Western civilization: Ancient Greece, C. 800-300 BCE.
7.34 Describe the purposes and functions of development of Greek institutions such as the lyceum, the gymnasium, and the Library of Alexandria, and identify the major accomplishments of the ancient Greeks.

WHI.33 Summarize how the Scientific Revolution and the scientific method led to new theories of the universe and describe the accomplishments of leading figures of the Scientific Revolution, including Bacon, Copernicus, Descartes, Galileo, Kepler, and
Newton.

A FRAMEWORK FOR K-12 SCIENCE EDUCATION: Practices, Crosscutting Concepts, and Core Ideas
PS2.A: FORCES AND MOTION
How can one predict an object’s continued motion, changes in motion, or stability?

Interactions of an object with another object can be explained and predicted using the concept of forces, which can cause a change in motion of one or both of the interacting objects… At the macroscale, the motion of an object subject to forces is governed by Newton’s second law of motion… An understanding of the forces between objects is important for describing how their motions change, as well as for predicting stability or instability in systems at any scale.

Discovery of conservation of momentum

You can explore this history-oriented lesson by Prof. Michael Fowler.

Momentum, Work and Energy Michael Fowler, U. Va. Physics

In 530 A.D., working in Alexandria, Byzantine philosopher John Philoponus developed a concept of momentum in his commentary to Aristotle’s Physics. Aristotle had claimed that everything that is moving must be kept moving by something. For example, a thrown ball must be kept moving by motions of the air.

Aristotle bust

Most writers continued to accept Aristotle’s theory until the time of Galileo, but a few were skeptical.

Philoponus pointed out the absurdity in Aristotle’s claim that motion of an object is promoted by the same air that is resisting its passage.

He proposed instead that an impetus was imparted to the object in the act of throwing it.

Ibn Sina (Arabic ابن سینا‎) (known by his Latinized name, Avicenna) read Philoponus and published his own theory of motion in The Book of Healing in 1020. He agreed that an impetus is imparted to a projectile by the thrower – but unlike Philoponus, who believed that it was temporary, and would decline even in a vacuum – Ibn Sina viewed it as a persistent. He understood that it required external forces – such as air resistance – to dissipate it.

Avicenna

These ideas were refined by European philosophers Peter Olivi and Jean Buridan. Buridan, who in about 1350 was made rector of the University of Paris, referred to impetus as proportional to the weight times the speed.

Like Ibn Sīnā, Buridan held that impetus (momentum) would not go away by itself; it could only dissipate if it encountered air resistance, friction, etc.

http://www.slideshare.net/StephenKwong1/part-1-world-in-motion

http://www.slideshare.net/StephenKwong1/part-1-world-in-motion

http://www.slideshare.net/StephenKwong1/part-1-world-in-motion

http://www.slideshare.net/StephenKwong1/part-1-world-in-motion

René Descartes believed that the total “quantity of motion” in the universe is conserved: quantity of motion = size and speed.

But Descartes didn’t distinguish between mass and volume, so this is not a specific equation.

Leibniz, in his “Discourse on Metaphysics”, gave an experimental argument against Descartes’ idea of “quantity of motion”.

Leibniz dropped blocks of different sizes, different distances.

He found that [size speed] did not yield a conserved quantity.

Gottfried_Wilhelm_von_Leibniz

The first correct statement of conservation of momentum:
English mathematician John Wallis, 1670
Mechanica sive De Motu, Tractatus Geometricus:

Isaac Newton’s Philosophiæ Naturalis Principia Mathematica, 1687

Defined “quantity of motion”, as “arising from the velocity and quantity of matter conjointly”
-> mass x velocity – which identifies it as momentum.

Isaac Newton

Adapted from “Momentum.” Wikipedia, The Free Encyclopedia. 2 Oct. 2015.

External resources

The cause of motion from Aristotle to Philoponus

The cause of motion Descartes to Newton

Learning Standards

2016 Massachusetts Science and Technology/Engineering Curriculum Framework

HS-PS2-2. Use mathematical representations to show that the total momentum of a system of interacting objects is conserved when there is no net force on the system. Emphasis is on the qualitative meaning of the conservation of momentum and the quantitative understanding of the conservation of linear momentum in
interactions involving elastic and inelastic collisions between two objects in one
dimension.
HS-PS2-3. Apply scientific principles of motion and momentum to design, evaluate, and refine a device that minimizes the force on a macroscopic object during a collision. Clarification Statement: Both qualitative evaluations and algebraic manipulations may be used.

Common Core Math

  • CCSS.MATH.CONTENT.7.EE.B.4  Use variables to represent quantities in a real-world or mathematical problem, and construct simple equations and inequalities to solve problems by reasoning about the quantities.
  • CCSS.MATH.CONTENT.8.EE.C.7  Solve linear equations in one variable
  • CCSS.MATH.CONTENT.HSA.SSE.B.3  Choose and produce an equivalent form of an expression to reveal and explain properties of the quantity represented by the expression. (including isolating a variable)
  • CCSS.MATH.CONTENT.HSA.CED.A.4  Rearrange formulas to highlight a quantity of interest, using the same reasoning as in solving equations. For example, rearrange Ohm’s law V = IR to highlight resistance R.
  • http://www.corestandards.org/Math/