Sunday, December 19, 2010

Albert Abraham Michelson

Albert Abraham Michelson was born on December 19, 1852 in Strenlo, Prussia (now Poland). His family moved two years later to Virginia City, Nevada where his father was a merchant. The family later moved to San Francisco, California, where Michelson first attended public school. He graduated in 1869 and President Ulysses S. Grant appointed him to the United States Naval Academy from which he graduated in 1873 and served for two years as an ensign on a cruise of the West Indies. After the cruise he he returned to the Naval Academy teaching chemistry and physics. In 1879 he was posted to the Naval Almanac Office. A year later he obtained a leave of absence so that he could go to Europe to continue his education where he visited the universities of Berlin and Heidelberg, and the College de France and the Ecole Polytechnique in Paris.

Michelson was fascinated with the speed of light. While at Annapolis he had repeated the Jean Bernard Leon Foucault's 1850 measurement, improving Foucault's rotating mirror system. After two years of studying in Europe he resigned from the Navy in 1881. In 1883 he took a position as a professor of physics at the Case School of Applied Science in Cleveland, OH. There he concentrated on developing an interferometer to use in his experiments.

In 1887 he performed, with Edward Morley, the experiment for which he is most famous. At the time it was believed that the earth (and everybody on it) was traveling through the aether, and electromagnetic waves (light) were affected by the movement of the aether. In order to test this effect Michelson and Morely used a light beam that was split in half and half was reflected in a right angle to the original beam. The light beams were then reflected back to the starting point where the interferometer was used to determine their velocities. The result was a null result and both light beams, traveling identical distances had both arrived back at the starting point at the same time, thus had equal velocities. This result proved that there was no aether and light could propagate at the same speed in any direction. For this work Michelson was awarded the Nobel Prize in 1907, becoming the first American to win the prize.

In 1889 Michelson moved to Clark University in Worcester, MA and in 1892 he was appointed professor of physics at the new University of Chicago. He continued his attempts to measure the speed of light and developed a way to use interferometry to determine the diameter of stars. In addition to the Nobel he has also won the Copley medal, the Henry Draper Medal and a gold medal from the Royal Astronomical Society. For his work he was awarded several honorary degrees and a crater on the moon is named after him

He died on May 9, 1931.


Law, Fredrick Houk; Modern Great Americans: Short Biographies of 20 Great Americans of Modern Times Who Won Wide Recognition for Achievements in Various Types of Activity; Ayer Publishing, 1969

Albert A. Michelson, Nobel Biography

Albert Abraham Michelson Wikipedia Entry

Sunday, December 12, 2010

William Henry

William Henry was born in Manchester, England on December 12, 1775. He was the son of Thomas Henry an apothecary and a founder of the Manchester Literary and Philosophical Society. Henry's early education took place at the Manchester Academy and he was apprenticed to Thomas Percival, a physician. As a boy he suffered an injury, caused by a beam falling on him, which left his growth stunted and caused pain. Because of the injury Henry would later abandon medical practice and instead devote his time to laboratory research. Dr. Percival had poor eyesight and was prone to headaches so he had Henry read to him. After a five year apprenticeship Henry went to Edinburgh University, where he studied medicine. While at Edinburgh he also attended the chemistry lectures of Joseph Black. He attained his M.D. in 1807.

While studying medicine Henry was also doing chemistry research. At the time it was believed that all acids contain oxygen and Henry attempted to remove oxygen from muriatic (hydrochloric) acid by electrocution. He was of course unsuccessful. When in 1810 Humphrey Davy proved that muriatic acid contained only hydrogen and chloride, Henry supported him, publishing a paper with further evidence in 1812. In 1802 he published an experiment where he measured the amount of dissolved gas in a liquid at different temperatures he showed that as the temperature drops the amount of dissolved gas increases.

He is most famous for discovering that the amount of a gas dissolved in a liquid is proportional to the partial pressure of the gas above the liquid. This is known as Henry's law. An example of how this law applies can be seen in canned or bottled carbonated soda. Before the can or bottle is opened the gas over the liquid is almost all carbon dioxide and the liquid contains dissolved carbon dioxide. When the can or bottle is opened the carbon dioxide over the drink is released and bubbles of carbon dioxide appear in the drink. As the partial pressure above the liquid is lowered (when the can or bottle is opened and exposed to the air) the dissolved carbon dioxide in the drink comes out of solution, producing bubbles. If the bottle or can is left to go to equilibrium almost all of the carbon dioxide will leave the liquid, and the soda will go flat.

Henry won the Copley Medal in 1808 and was elected a fellow of the Royal Society in 1809. In 1801 he published "An Epitome of Chemistry", later renamed "The Elements of Experimental Chemistry", which went through eleven editions and was last published in 1829.

He died on September 2, 1836.

"William Henry" in The Dictionary of National Biography; Leslie Stephen and Sidney Lee, Editors; Macmillian Compan; 1908

William Henry Wikipedia Entry

Monday, December 6, 2010

Carl Ferdinand Cori

Carl Ferdinand Cori was born on December 5, 1896 in Prague, then part of Austria-Hungary. There were university professors on both sides of his family; his maternal gradfather was theoretical physicist Ferdinand Lipich and father was a marine biologist. He moved with his family to Trieste when he was two, where his father was the director of the Marine Biological Station. Young Cori's interest in science was sparked by his father, who took him on expeditions to collect samples. Young Cori was also a practical joker, one time planting silk worms in his mother's parlor, timed so that the moths would escape their cocoons during a party his mother was throwing. His mother was mortified. After graduating from gymnasium, in 1914, Carl went to study medicine at the Charles-Ferdinand University in Prague. During World War I he served as a lieutenant in the ski corps. and sanitary corps. on the Italian front. After the war he returned to the university where he finished his medical education and met his wife Gerty who was also a medical student.

After a year as an assistant in pharmacology at the University of Graz, he and his wife emigrated to America, where he took a position as a biochemist at the State Institute for the Study of Malignant Diseases in Buffalo, New York. In 1928 the Coris became naturalized American citizens and in 1931 he was appointed professor of pharmacology in the medical school at Washington University in St. Louis. The Coris, Carl and Gerty, collaborated on their research, starting in their student days.

At first their research was on immunology, but they switched the topic of their research to study the fate of sugar in the human body. In 1936 they succeeded in isolating glucose-1-phosphate, a key intermediate in sugar metabolism. Once glucose enters the cell, phosphate is added to it enzymatically, forming glucose-1-phosphate. With the negatively charged phosphate group attached to it, glucose is then unable diffuse through the lipid bilayer of the cell membrane, keeping glucose sequestered within the cell, where it may be broken down to release energy. The Coris also studied how glucose can be reversibly stored for later use as glycogen and discovered the enzymes responsible. For their discovery of how glycogen is produced they were awarded half of the Nobel Prize of Physiology and Medicine in 1947.

Gerty Cori died in 1957 and Carl retired from Washington University in 1966. After retirement he moved to Cambridge, Massachusetts where he worked on genetic research at Harvard University.

Cori died on October, 24, 1984.


Cori, Carl F.; "The Call of Science"; Annual Review of Biochemistry (1969)38:1-21

Carl Ferdinand Cori Wikipedia Entry

Carl Cori Nobel Biography