In 1775 scientists sat in a 127°C room and found sweat, not the air, kept their bodies cool

science & techThe Public Domain Review1774–1775 · London, England

In 1775 scientists sat in a 127°C room and found sweat, not the air, kept their bodies cool

the gist

In 1774 and 1775, the physician Charles Blagden and colleagues sat in a room heated far beyond what anyone thought a living body could bear, eventually reaching 127°C. A dog endured 113°C for an hour and recorded a body temperature of about 43°C, far cooler than the air around it. Blagden was the first to clearly identify perspiration as the reason, since sweat evaporating from the skin draws away heat. To check his thermometers, he cooked eggs and beef steaks in the same room, which roasted within minutes. Blagden's report went to the Royal Society in London.

how it works

Sweat is produced by glands and spreads onto the skin, where it evaporates. Evaporation takes heat energy from the skin, so the body stays cooler than the surrounding air as long as sweat can evaporate. Moving air speeds this up, which is why a fan helps.

so what

Blagden's experiments were a key step in understanding human thermoregulation, showing that the body's cooling depends on evaporation and that the air's temperature alone does not decide how hot a body gets.

fun fact

Charles Blagden later served as secretary of the Royal Society.

D. W. Griffith’s A Corner in Wheat (1909)

the gist

In 1909 D. W. Griffith made a 14-minute film about a speculator who corners the wheat market and doubles the price of bread. A farmer sows his field while a 'Wheat King' gambles in the Chicago wheat pit; bakers raise the loaf from five cents to ten and the poor line up for bread. Griffith cut back and forth between the farm, the feast and the breadline, a technique called parallel editing, so audiences saw both ends of the economy at once. The film drew on Frank Norris's stories and on a real scheme: months earlier Chicago financier James Patten had cornered wheat, sent bread prices up and made about $5 million, roughly $185 million today.

how it works

To corner a market, a trader buys up most of the available supply and the futures contracts that promise more. Anyone who has to deliver the commodity must then buy from the cornerer at whatever price is demanded. The trader profits until the stock is released or the scheme collapses.

so what

A century on, it still shows how markets can be rigged by someone who controls supply, and how the people at either end, farmers and eaters, pay for it. It also helped establish editing as a way to argue a point, not just tell a story.

the bigger pattern

Corners have recurred whenever supply could be locked up, from the Hunt brothers' attempt on silver in 1979 to 1980 to the 'Black Friday' gold panic of 1869. Many such schemes end by collapsing, and the response is often new rules on speculation.

fun fact

In the film the Wheat King dies by falling into a grain elevator and being buried in the wheat he hoarded, an ending borrowed from Norris's novel The Octopus.

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