August 1964 Liquid Crystals “Although their existence has been known for more than 70 years, substances that exhibit the liquid-crystal phase have until recently been regarded more as laboratory curiosities than as potentially useful or theoretically important objects of study. In the past few years, however, several investigators in this country and abroad have undertaken to reexamine the liquid-crystal phase. The first results of these new studies have helped to clarify the unusual molecular architecture of liquid crystals. They also point to a number of possible applications that arise from the remarkable ability of liquid-crystal substances to register minute fluctuations in temperature, mechanical stress, electromagnetic radiation and chemical environment by changing their color.”
On supporting science journalism
If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.
August 1914 The Great War “Not since wars began has so great a military people, with such a sublime confidence in its invincible prowess, played for so great a stake as that for which the German hosts are now battling on sea and land. Should the Teuton win, he will hold all Europe in his ‘mailed fist,’ and the flag of his ships of war and commerce will float undisputed upon the Seven Seas, with nothing to stand between him and worldwide dominance but the great English-speaking republic of the New World! Had Germany shown a less ruthless spirit in flinging herself against the rest of Europe in a defiance so bold as to appear almost contemptuous, she might hope, in the event of disaster, for reasonable terms in the great final accounting. As it is, Europe, if victorious, will take a heavy toll.”
Images and articles on World War I from our archives are at ScientificAmerican.com/wwi
Fix for Hair Loss “A hair planting method employed by Dr. Szekely in Buda-Pesth is claimed to be a practical one. A gold wire 1/500 inch in diameter is bent to form a loop, barely visible to the naked eye, which is threaded with a woman's hair of the desired color and from 8 to 12 inches long. The wire is introduced into a short, fine Pravaz hypodermic needle and then bent and cut, forming a tiny hook. The needle is inserted normally, twisted and carefully withdrawn. The doubled hair is anchored by the hook in the subcutaneous tissue. As many as 50,000 hairs may be required for an entirely bald head [see illustration]. Even in this case little more than 15 grains of gold is consumed.”
Superconductivity “In studying the resistances of metals at temperatures that one may obtain with liquid helium, I foresaw that the resistance of mercury would still be easy to measure at 4.25 degrees Kelvin, but would diminish so as to become negligible at 2 deg. Kelvin (–271 deg. Centigrade). Experiments have verified this prediction so far as low temperatures are concerned, but they have also brought to light the fact that the disappearance of the resistance is sudden. The mercury at the temperature of the fall, here termed critical temperature (4.19 deg. Kelvin), passes in a disconnected way into a new state that is characterized by an extreme mobility of electricity. It may be well to term this condition, in which it is possible to maintain currents without appreciable electromotive force, the state of superconductivity.—H. Kammerlingh Onnes”
August 1864 California Ants “That enemy of the hoarded sweets of the California housekeeper, the ant, is beyond counting in his annoyances this year. In the warmer districts of the State nothing eatable can be stored without attracting myriads of them, and the destruction they cause is really an important item. They have never within memory of the oldest settlers been so numerous in the lower levels of the Sacramento and San Joaquin as in 1864, and in the mines, residents inform us they invade in armies every pantry, kitchen and closet. The miners say they are laying up an early stock of comestibles to pass a long and heavy winter!”
MORE TO EXPLORE
Find original articles and images in the Scientific American archives at ScientificAmerican.com/magazine/sa
Scientific American Online For the 100th anniversary of the Panama Canal, see a slide show at ScientificAmerican.com/aug2014/panama
