Cavendish, Charles

Henry Cavendish was descended from the dukes of Devonshire on one side and from the dukes of Kent on the other. His father, Lord Charles Cavendish, was either the third or the fifth son of the second duke of Devonshire. His mother, Lady Anne Grey, was the daughter of Henry, duke of Kent. She was not in robust health when she married, and she died when Henry was only two years old. 

Lord Charles Cavendish might not have been wealthy, but he was a natural philosopher and experienced experimentalist. Indeed his research on heat, electricity, and magnetism earned him praise from Benjamin Franklin. Henry must have learned a lot from his father, because he, too, became a meticulous experimenter. Some of Henry s experiments in physics and most of his chemical experiments were performed while he was still living under his father s roof. 

In 1798 the Committee of Privy Council for considering the state of the coinage reported that the gold coin was suffering considerable losses in weight, and requested Henry Cavendish and Charles Hatchett to examine it to ascertain whether this loss was occasioned by any defect (13). Their experiments were begun near the end of 1798 and completed in April, 1801. At Cavendish s request the report was made... 

Apparatus Designed by Henry Cavendish and Used by Charles Hatchett for Determining the Comparative Wear of Gold When Alloyed by Varions Metals. Two frames, one above the other, each carrying twenty-eight coins, rubbed the upper coins backward and forward over the ones below. Each of the smaller concentric circles represents a coin. To avoid the formation of furrows, the direction in which the coins rubbed against each other was made to vary continually. 

Letter to Thomas Graham, as quoted by William Charles Henry, Memoirs of the Life and Scientific Researches of John Dalton (London Cavendish Society, 1854), 124. 

The earliest, and I think so far unnoticed, record of an attempt by Watt to diagnose experimentally the chemical state of the steam inside a working engine is contained in an eyewitness report by Henry Cavendish. In early August 1785 Cavendish and his assistant Charles Blagden visited the Soho works of Boulton Watt at Birmingham. They were shown Watt s latest experiments on the steam engine, and Cavendish recorded the experience ... 

Cavendish s results were the same as Priestley s, but he did not publish or present his findings. Sometime before 1783, however, Cavendish did advise Priestley of his results. Priestley told Charles Blagden, secretary of the Royal Society in London, and Blagden in turn informed Antoine Lavoisier (1743-1794) in Lrance. 

While most of Charles s papers were on mathematics, he was ultimately an avid scientist and inventor. He dupficated a number of experiments that Franklin and others had completed on electricity and designed several instruments, including a new type of hydrometer for measuring densities and a reflecting goniometer for measuring the angles of crystals. Charles was elected to France s Academy of Sciences in 1785 and later became professor of physics at the Conservatoire des Arts et Metiers. He died in Paris on April 7, 1823. see also Boyle, Robert Cavendish, Henry Dalton, John Gay-Lussac, Joseph-Louis. 

Barkla, Charles Glover (1877-1944) was born in Widnes, Lancashire, England. After obtaining his master s degree in physics he went to work in the Cavendish Laboratory with J.J. Thomson. In 1913 he accepted the position of Chair in Natural Philosophy in the University of Edinburgh in Scotland and he remained there until he died. He was awarded the 1917 Nobel Prize in Physics for his discovery of the characteristic Rbntgen radiation of the elements. 

In 1783 Cavendish s assistant, Charles Blagden, visited Paris and told Lavoisier about Cavendish s work. Lavoisier rapidly repeated the experiments, and interpreted them in terms of his antiphlogistic theory by stating that water is a compound of inflammable air and oxygen (Chapter 5). 

Once again Lavoisier received a hint from a traveller from England. This time it was Charles Blagden, Cavendish s assistant, who visited Lavoisier in June 1783 and described Cavendish s quantitative experiments in which he had reacted two volumes of inflammable air with one of dephlogisticated air and found that in this... 

This work anticipated that published by Faraday. Cavendish s paper on the Royal Society s instruments dealt not only with thermometers but also with the effect of capillarity on the height of mercury in a barometer tube and the correction for temperature, the rain-gauge, hygrometer, dipping needle, and variation compass. It contains careful observations on the construction and calibration of mercury thermometers. Lord Charles Cavendish had previously described what is essentially a Beckmann thermometer with a variable zero. Cavendish constructed an ingenious registering (maximum and minimum) thermometer, which is now in the Royal Institution. ... 

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