Historical past: November 2023 – Scientific American


1973

Mayan Astronomers Predicted Eclipses

“The Maya have been expert naked-eye astronomers. It now appears that they might even forecast eclipses of the solar. That’s the conclusion of a brand new evaluation of the ‘Venus Desk’ and the ‘Lunar Desk’ contained within the Maya e book the Dresden Codex. Calculating in multiples of their very own 260-day ‘sacred 12 months,’ Maya astronomers seem to have detected two completely different sorts of periodicity within the recurrence of eclipses: a ‘quick’ interval of 9,360 days (36 sacred years) and a ‘lengthy’ interval of 11,960 days (46 sacred years). For photo voltaic eclipses seen in Central America, the desk would have offered passable predictions from A.D. 42 to 886.”

Sourdough Micro organism

“Early prospectors within the American West carried the substances of a extremely acidic bread that earned them the title ‘sourdoughs.’ The bread is now baked commercially in San Francisco, however solely not too long ago was the organism accountable for its attribute sourness recognized. Leo Kline and T. F. Sugihara of the U.S. Division of Agriculture discovered a fortuitous mixture of a yeast—Saccharomyces exiguus—and a bacterium, apparently of the genus Lactobacillus. For speedy development the micro organism require the sugar maltose, from which they produce lactic acid and acetic acid, which account for the bitter style. The yeast is tolerant of this acidic atmosphere, and it ferments carbohydrates apart from maltose to provide the carbon dioxide that leavens the bread. The title proposed for the brand new species is Lactobacillus sanfrancisco.

1923

Anesthesia From Sleeping Flowers

“Way back to 1908 florists complained that carnations when positioned in greenhouses would fall asleep, and people which had not opened would fail to take action, inflicting nice loss of their enterprise. Investigation proved that ethylene from leaky fuel fixtures was the trigger. This led Dr. Luckhardt and Mr. Carter of the College of Chicago not too long ago to check the fuel as an anesthetic. The fuel was tried first on quite a few animals. The experimenters then tried it on themselves. They describe the impact of the fuel combined with oxygen as giving a way of well-being. They grew to become unconscious after which recovered. A number of college students then volunteered. Topics had pins thrust by their arms, and have been pinched severely sufficient to depart black and blue areas. It’s claimed that the brand new anesthetic offers lack of sensation with none signal of asphyxia, shortness of breath or impact upon the blood strain. The one after-effect was slight weak point and slight nausea.”

No Neutrons (But)

“Now we have steadily learnt that electrical energy exists in two varieties, the damaging type, which known as an electron, and the constructive type, which is now starting to be referred to as a proton. The fabric universe appears to be constructed of those two parts. Each the electron and the proton are very a lot smaller than an atom of matter. Each most likely have weight, although the proton weighs as a lot as 1,830 electrons. However it’s not appreciably greater. The very fact is, we have no idea a lot about it. Whether or not the proton is an final unit, or whether or not it may be resolved right into a close-packed assemblage of easier substances, which might account for its outstanding weight or massiveness, stays for future discovery.”

1873

Can Birds Sense Cholera?

“It’s possible that birds, in some method, turn out to be conscious of cholera an infection within the air. Latest European journals state that at Munich, the place a number of circumstances of cholera have occurred, the rooks and crows, which flew concerning the steeples and thru the timber of the general public promenades, have all emigrated. The identical factor occurred throughout the cholera seasons of 1836 and 1854. The identical phenomena occurred at Mauritius, the place the martins, which exist in immense numbers the 12 months spherical, wholly disappeared throughout the prevalence of the cholera.”

Covers of Scientific American from November 1973, 1923 and 1873.



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