Monthly Archives: February 2015

Brass monkey cold

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In case it should ever come up in conversation, only the picture at left shows a brass monkey. The other is a bronze statue of some sort of a primate. A brass monkey is a rack used to stack cannon balls into a face centered pyramid. A cannon crew could fire about once per minute, and an engagement could last 5 hours, so you could hope to go through a lot of cannon balls during an engagement (assuming you survived).

A brass monkey cannonball holder. The classic monkeys were 10 x 10 and made of navy brass.

Small brass monkey. The classic monkey might have 9 x 9 or 10×10 cannon balls on the lower level.

Bronze sculpture of a primate playing with balls -- but look what the balls are sitting on: it's a surreal joke.

Bronze sculpture of a primate playing with balls — but look what the balls are sitting on: it’s a dada art joke.

But brass monkeys typically show up in conversation in terms of it being cold enough to freeze the balls off of a brass monkey, and if you imagine an ornamental statue, you’d never guess how cold could that be. Well, for a cannonball holder, the answer has to do with the thermal expansion of metals. Cannon balls were made of iron and the classic brass monkey was made of brass, an alloy with a much-greater thermal expansion than iron. As the temperature drops, the brass monkey contracts more than the iron balls. When the drop is enough the balls will fall off and roll around.

The thermal expansion coefficient of brass is 18.9 x 10-6/°C while the thermal expansion coefficient of iron is 11.7 x10-6/°C. The difference is 7.2×10-6/°C; this will determine the key temperature. Now consider a large brass monkey, one with 400 x 400 holes on the lower level, 399 x 399 at the second, and so on. Though it doesn’t affect the result, we’ll consider a monkey that holds 12 lb cannon balls, a typical size of 1750 -1830. Each 12 lb ball is 4.4″ in diameter at room temperature, 20°C in those days. At 20°C, this monkey is about 1760″ wide. The balls will fall off when the monkey shrinks more than the balls by about 1/3 of a diameter, 1.5″.

We can calculate ∆T, the temperature change, °C, that is required to lower the width-difference by 1.5″ as follows:

kepler conjecture, brass monkey

-1.5″ = ∆T x 1760″ x 7.2 x10-6

We find that ∆T = -118°C. The temperature where this happens is 118 degrees cooler than 20°C, or -98°C. That’s a temperature that you could, perhaps reach on the South Pole or maybe deepest Russia. It’s not likely to be a problem, especially with a smaller brass monkey.

Robert E. Buxbaum, February 21, 2015 (modified Apr. 28, 2021). Some fun thoughts: Convince yourself that the key temperature is independent of the size of the cannon balls. That is, that I didn’t need to choose 12 pounders. A bit more advanced, what is the equation for the number of balls on any particular base-size monkey. Show that the packing density is no more efficient if the bottom lawyer were an equilateral triangle, and not a square. If you liked this, you might want to know how much wood a woodchuck chucks if a woodchuck could chuck wood, or on the relationship between mustaches and WWII diplomacy.

Detroit emerges from bankruptcy. Not quite.

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missing homes Detroit

While Detroit’s central core comes back, surrounding, homes burn at 220+/month, leave Detroit streets looking like the teeth of an aging hillbilly.

Detroit went bankrupt last year, the largest US city to do so since New York in 1970. As with New York’s bankruptcy, Detroit’s was used to cancel old debts and rewrite ill-thought contracts. Detroit also got to jail some crooked politicians including mayor Kilpatrick, described as “a walking crime wave.” But the city and county have no easy path out of bankruptcy as both city and county are likely insolvent. That is, they spend more than they take in despite massive out-state funding, and high taxes, 10% above the state level. To make matters worse, they are losing population at the rate of 1% or so per year. It’s hard to fund a city built for 2 million on the tax revenue of 1/3 as many, especially when they are mostly unemployed. Unless a lot changes soon, another bankruptcy is almost inevitable — likely this time at the county level.

We got in this state, largely as a result of a 50 year war between the black, solidly Democrat, somewhat anarchist, political establishment of Detroit, and the white, stayed, mostly Republican out state. The white population fled following the riots of the 60s and the richer black population soon followed. The remainder stayed, trapped in slowly decaying neighborhoods as the city went broke. White flight allowed the black community to develop its own, Motown culture, but except for the music industry, it has not benefitted from this culture.

Detroit's murder rate, 45/100,000, is the highest in the US. It's coming down but not that fast.

Detroit’s murder rate is the highest in the US. It’s come down 10% in the last 2 years, but has far to go.

Detroiters have poor health, poor savings rates, high murder rates, and a fire rate of about .22% per month, 2.6% per year. The city lacks basic city services like reliable fire fighting and street plowing. Police at one point erected signs that said, “enter at your own risk.” There is a lack of small businesses and the services they would provide too: laundromats, grocery stores, and taxis (though no lack of bars and marijuana maintenance clinics). Employment in the auto-industry is down. And it’s not being replaced by home-grown small business – perhaps hampered by the low savings rate. A surprisingly large fraction of the Detroit homes are in foreclosure, see map, and with it a high abandonment rate and a high fire rate. As pheasant and dear return, non-core Detroit is beginning to look like farm country.

Detroit foreclosures near me. Blue is occupied homes, red is unoccupied, yellow unknown, and green is destroyed homes or vacant, foreclosed land.

Detroit foreclosures near me. Homes in dark blue are occupied foreclosed, red is unoccupied, and green plots are destroyed homes or vacant, foreclosed land.

It’s not clear what political leaders should do. The city council would like to return to their pre-bankruptcy ways where they could borrow as much as they felt they needed and spend on whatever they saw fit — often on fast friends, fast cars, gambling, and vacation homes outside of the city. But the out-state population has been reluctant to give them the credit card. Is this racist or is it prudent — probably both, but this can not continue. The city and county pension funds were ransacked for ill-advised investments and consulting fees to cronies and their power-lawyers. Either the money is replaced from out-state or there will be some unhappy retirees in the not-too-distant future. My guess is that the state will have to pick up the tab for this mismanagement, but that they won’t want to hand over management control afterwards.

Rand Paul, a potential GOP presidential candidate, has proposed rebuilding business and property values by a method that the city will almost certainly reject. His solution: cut services to low-population density areas and cut taxes on business and earned income. While this would likely bring in new people and new businesses, the people would likely be white, and the businesses white-owned/ white-serving. Black-Detroiters have too little savings, organization and income to directly benefit from this plan. Detroit’s Democrat politicians will claim, not without merit, that this is welfare for rich whites: a way for them to become yet-richer while doing nothing for the poor blacks of the burning neighborhoods. They are likely to demand control as the elected officials of the town: regulating business and raising the minimum wage to create “equality.” I suspect this is a bad idea.

Detroit hunger games

Detroit suffers from two populations and a divide.

To some extent we’re already seeing the return of white-owned, white-serving businesses. Classic buildings in the core of the city have been purchased by white developers – notably Dan Gilbert of Quicken Loans leading to gentrification and an influx of single, white hipsters. The newcomers are viewed as half-saviors, half-carpetbaggers. They dwell in a whiter city core with hipster bars and expensive restaurants. Does a poor city with massive debt, crime, and unemployment benefit from a core filled with high-priced, gourmet coffee and fern bars?

The author, Robert Buxbaum, enjoys a day at an artificial beach in central Detroit.

The author, Robert Buxbaum, enjoys a beer at an artificial beach-cafe in central Detroit with some, few black folks, none poor. Is this good for Detroit?

The new hipsters put a squeeze on city services too — one that’s hard to deal with fairly. Detroit can not afford to plow all the streets after a snow. Should the new high-tax white folks get plowed streets, or should they suffer equally with everyone else? Detroit education is abysmal, but the high tax-bracket folks want better. Should they get it, or suffer equally? They want extra street lights and police protection. Should they get it, or suffer equally? Is this the way up?  A solution I’d proposed some while ago was to divide the core city from the now-rural outskirts so that each could be managed more sanely. It’s not a grand a solution like Rand’s plan, but less likely to be rejected. One way or another, we seem destined to have a Detroit with a rich core and abandoned neighborhoods. I suspect it might as well be managed that way.

Robert E. Buxbaum, February 10, 2015. I don’t have solutions, but write about the city’s problems, and the partial solutions I’ve heard as a way to clarify my thinking — and perhaps yours too.

you are what you eat?

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The simplest understanding of this phrase is that you should eat good, healthy foods to be healthy, and that this will make you healthy in body and mind.

The author of the study published this book against GM foods simultaneously with release of his paper.

The author of this book against unhealthy foods faked his analysis to support the book.

Clearly there is some truth to this. Crazy people look crazy and often eat crazy. Even ‘normal’ people, if they eat too much are likely to become fat, lazy, and sick. There is a socio- economic effect (fat people earn less), and a physiological evidence that gut bacteria affects anxiety and depression (at least in rats). My sense here is at the diet extremes though. There is little, or no evidence to suggest you can make yourself more intelligent (or kind or good) by eating more of the right stuff, or just the right foods in just the right amounts. A better diet can make you look better, but there is a core lie at work when you extend this to imply that the real you is your body, or so tied to your body that a healthy mind can not be found in a sickly body. But most evidence is that the mind is the real you, and (following Socrates) that beautiful minds are found in sickly bodies. I’ve seen few (basically, no) healthy poets, writers, or great artists. Neither are there scientists of note (that I can recall) who lived without smoking, drinking, and any bad habits. Many creative people did drugs. George Orwell smoked cigarette, and died of TB, but wrote well to the end. There is no evidence that bad writing or thinking can be improved by health foods. Stupid is as stupid does, and many healthy people are clearly dolts.

Not that it’s always clear what constitutes good health, or what constitutes good food for health, or what constitutes a good mind. Skinny people may be admired and may earn more, but it is not clear they are healthy. Yule Gibbons, the natural food guru died young of stomach cancer. Adele Davis, another the author of “eat right to be healthy,” died of brain cancer. And Jim Fix, “the running doctor” died young of a heat attack while running. Their health foods may have killed them, and that unhealthy foods, like chocolate and coffee can be good for you. It’s likely a question of balance. While a person will feel better who dresses well, the extreme is probably no good. Very often, a person is drawn after his self-image to be the person he pretends. Show me a man who eats only vegetarian, and I’ll show you someone who sees himself as spiritual, or wants to be seen as spiritual. And that man is likely to be drawn to acting spiritual. Among the vegetarians you find Einstein, George B. Shaw, and Gandhi, people who may have been spiritual from the start, but may have been kept to spirituality from their diets. You also find Hitler: spirituality can take all sorts of forms.

Ward Sullivan in the New Yorker

Ward Sullivan in the New Yorker. People eat, drink, and dress like who they are. And people become like those they eat drink and dress like.

Choice of diet also helps select the people you run into. If you eat vegetarian, you’re likely to associate with other vegetarians, and you will likely behave like them. If you eat Chinese, Greek, or Mexican food, you’re likely to associate with these communities and behave like them. Similarly, an orthodox Jew or Moslem is tied to his community with every dinner and every purchase from the kosher or halal store.

And now we come to the bizarre science of bio-systems. Each person is a complex bio-system, with more non-human DNA than human, and more non-human cells than human. A person has a vast army of bugs on him, and a similarly vast pool of bugs within him. Recent research suggests that what we eat affects this bio-system, and through it our mental state. For whatever the mechanism, show me someone who drinks only 30 year Scotch or 40-year-old French wine, and I’ll show you a food snob. By contrast, show me someone who eats good, cheap food, and drinks good, cheap wine or Scotch (Lauder’s or Dewar’s), and I’ll show you a decent person very much like myself, a clever man who either is a man of the people or who wants to be known as one.”Dis-moi ce que tu manges, je te dirai ce que tu es.” [Tell me what you eat and I will tell you what you are].

Robert E. Buxbaum, February, 2015. My 16-year-old daughter asked me to write on this topic. Perhaps she didn’t know what it meant, or how true I thought it was, or perhaps she liked my challenges of being 16.