Here’s a Throwback-Thursday with a twist. This one comes on Wednesday. Why, you ask? Just for the heck of it.
In our blog’s this segment, we take you back in time.
We shall cover some scientists that were born and some prominent events that happened in scientific history.
Have a good read!
TIMELINE– 30th May -5th June
RICHARD JULIUS PETRI– Born 31st May 1852
German physician and bacteriologist, remembered for his name given to the Petri dish. This is a shallow, cylindrical dish made of plastic or glass with a cover, used for tissue cultures and to hold solid media for culturing and sub-culturing bacteria. Petri developed it for a technique for cloning bacterial strains using an agar slope and sub-culturing onto his dish, recognizing different bacterial colonies and again sub-culturing. He was in his later days a rather vain, overweight man, who dressed in the uniform of chief army doctor whenever the opportunity presented itself. One observer remarked that the sash around his protuberant abdomen reminded him of the equator around the globe.
SADI CARNOT- Born 1 June 1796
Nicolas-Lèonard-Sadi Carnot was a French engineer and physicist became a captain of engineers in the army, and spent much of his life investigating the design of steam engines. His book Reflections on the Motive Power of Heat (1824) contained a theorem which says that a maximum efficiency of heat engine can be obtained by a reversible engine, and that efficiency depends only on the temperatures of the hot and the cool sources of the engine. This theorem played an essential role for the subsequent development of thermodynamics. It was written to promote the construction of steam engines and other heat engines in France, whose industrial development was lagging behind England’s.
THIS WEEK IN SCIENTIFIC HISTORY-
Krypton 30 May
In 1898, Morris William Travers, an English chemist, while working with Sir Willam Ramsay in London, discovered the element krypton. The name derives from the Greek word for “hidden.” It was a fraction separated from liquified air, which when placed in a Plücker tube connected to an induction coil yielded a spectrum with a bright yellow line with a greener tint than the known helium line and a brilliant green line that corresponded to nothing seen before.
Electric Railway 31 May
In 1879, the first electric railway opened at the Berlin Trades Exposition in Germany. It was the size of what today would be called a passenger-carrying miniature railway. The electric locomotive had a motor with about 3 horsepower, that was capable of hauling three small cars around a belt line 300 m (983 feet) long at up to 7 km (4.2 miles) per hour. Power at 150 volts was taken from a third rail between the running rails, which were bonded to serve for the return circuit. By 30 Sep 1879, it carried 86,398 passengers. The wooden covering over the motor provided a seat for the motorman. Gearing provided the ability to change direction of travel. Werner von Siemans and his firm of Siemens & Haslke was next able to build a line in Gross Lichterfelde, near Berlin, which opened for public use on 16 May 1881.
Doomsday clock 1 June
In 1947, the Doomsday Clock appeared for the first time, as the fourth quadrant of a clock face with its hands at 7 min. to midnight. It was the background image on the cover of the June issue of the Bulletin of the Atomic Scientists. From then to the present, the Doomsday Clock image has been on the cover of theBulletin, though the hands over the years have been shown moving forward or back to conveyy how close humanity is to catastrophic destruction. Midnight represents Doomsday. The closest approach, two minutes to midnight began on the Sep 1953cover. Russia’s first hydrogen bomb test the previous month (12 Aug 1953) within nine months of an American H-bomb test (1 Nov 1952). In Dec 1991, the clock was set at 17 min. to midnight marking the Strategic Arms Reduction Treaty.« [An actual publication date of 27 May 1947 might be deduced from a New York Times article on that date which referred to a report that “will appear today in The Bulletin of the Atomic Scientists.”
Publishing “Principia” 2 June
In 1686, the publication of Newton’s Principia was arranged in London at the Royal Society. The minutes of the meeting record that the astronomer Edmond Halley would “undertake the business of looking after it and printing it at his own charge.”
AIDS 5 June
In 1981, a epidemic disease, later to be named as AIDS, was briefly describedby Dr. Michael Gottlieb in the newsletter of the U.S. Centers for Disease Control. This was the first notice to be published on AIDS, though it had not yet been given that name. Gottlieb was in his first research position as assistant professor of medicine at the University of California at Los Angeles. Despite the medical profession’s refusal to acknowledge the AIDS crisis, he pursued early immune deficiency cases and urged the publication of his findings. He left UCLA in 1987 to open a private practice, he has devoted his career to treating AIDS patients and fostering AIDS research. He was one of the first researchers to test the drug AZT on AIDS patients.