53 Facts About Henry Cavendish

Henry Cavendish was an English natural philosopher and scientist who was an important experimental and theoretical chemist and physicist.

Henry Cavendish is noted for his discovery of hydrogen, which he termed "inflammable air".

Henry Cavendish described the density of inflammable air, which formed water on combustion, in a 1766 paper, On Factitious Airs.

Henry Cavendish's mother was Lady Anne de Grey, fourth daughter of Henry Grey, 1st Duke of Kent, and his father was Lord Charles Cavendish, the third son of William Cavendish, 2nd Duke of Devonshire.

Henry's mother died in 1733, three months after the birth of her second son, Frederick, and shortly before Henry's second birthday, leaving Lord Charles Cavendish to bring up his two sons.

Henry Cavendish then lived with his father in London, where he soon had his own laboratory.

Lord Charles Henry Cavendish spent his life firstly in politics and then increasingly in science, especially in the Royal Society of London.

In 1760, Henry Cavendish was elected to both these groups, and he was assiduous in his attendance after that.

Henry Cavendish took virtually no part in politics, but followed his father into science, through his researches and his participation in scientific organisations.

Henry Cavendish was active in the Council of the Royal Society of London.

In 1773, Henry Cavendish joined his father as an elected trustee of the British Museum, to which he devoted a good deal of time and effort.

About the time of his father's death, Henry Cavendish began to work closely with Charles Blagden, an association that helped Blagden enter fully into London's scientific society.

Henry Cavendish published no books and few papers, but he achieved much.

Henry Cavendish is considered to be one of the so-called pneumatic chemists of the eighteenth and nineteenth centuries, along with, for example, Joseph Priestley, Joseph Black, and Daniel Rutherford.

Henry Cavendish found that a definite, peculiar, and highly inflammable gas, which he referred to as "Inflammable Air", was produced by the action of certain acids on certain metals.

In 1777, Henry Cavendish discovered that air exhaled by mammals is converted to "fixed air", not "phlogisticated air" as predicted by Joseph Priestley.

Also, by dissolving alkalis in acids, Henry Cavendish produced carbon dioxide, which he collected, along with other gases, in bottles inverted over water or mercury.

Henry Cavendish then measured their solubility in water and their specific gravity, and noted their combustibility.

Henry Cavendish concluded in his 1778 paper "General Considerations on Acids" that respirable air constitutes acidity.

Henry Cavendish was awarded the Royal Society's Copley Medal for this paper.

In 1783, Henry Cavendish published a paper on eudiometry.

Henry Cavendish described a new eudiometer of his invention, with which he achieved the best results to date, using what in other hands had been the inexact method of measuring gases by weighing them.

Henry Cavendish concluded that rather than being synthesised, the burning of hydrogen caused water to be condensed from the air.

Henry Cavendish conducted experiments in which hydrogen and ordinary air were combined in known ratios and then exploded with a spark of electricity.

Henry Cavendish worked with his instrument makers, generally improving existing instruments rather than inventing wholly new ones.

Henry Cavendish, as indicated above, used the language of the old phlogiston theory in chemistry.

Henry Cavendish objected to Lavoisier's identification of heat as having a material or elementary basis.

Henry Cavendish made his objections explicit in his 1784 paper on air.

Henry Cavendish went on to develop a general theory of heat, and the manuscript of that theory has been persuasively dated to the late 1780s.

Henry Cavendish's theory was at once mathematical and mechanical: it contained the principle of the conservation of heat and even included the concept of the mechanical equivalent of heat.

The apparatus Henry Cavendish used for weighing the Earth was a modification of the torsion balance built by Englishman and geologist John Michell, who died before he could begin the experiment.

Henry Cavendish intended to measure the force of gravitational attraction between the two.

Henry Cavendish noticed that Michell's apparatus would be sensitive to temperature differences and induced air currents, so he made modifications by isolating the apparatus in a separate room with external controls and telescopes for making observations.

Henry Cavendish found that the Earth's average density is 5.48 times greater than that of water.

John Henry Poynting later noted that the data should have led to a value of 5.448, and indeed that is the average value of the twenty-nine determinations Cavendish included in his paper.

The result that Henry Cavendish obtained for the density of the Earth is within 1 percent of the currently accepted figure.

Henry Cavendish's work led others to accurate values for the gravitational constant and Earth's mass.

Lord Charles Cavendish died in 1783, leaving almost all of his very substantial estate to Henry.

Henry Cavendish published an early version of his theory of electricity in 1771, based on an expansive electrical fluid that exerted pressure.

Henry Cavendish demonstrated that if the intensity of electric force were inversely proportional to distance, then the electric fluid more than that needed for electrical neutrality would lie on the outer surface of an electrified sphere; then he confirmed this experimentally.

Henry Cavendish continued to work on electricity after this initial paper, but he published no more on the subject.

Henry Cavendish wrote papers on electrical topics for the Royal Society but the bulk of his electrical experiments did not become known until they were collected and published by James Clerk Maxwell a century later, in 1879, long after other scientists had been credited with the same results.

Henry Cavendish died at Clapham on 24 February 1810 and was buried, along with many of his ancestors, in the church that is Derby Cathedral.

Henry Cavendish inherited two fortunes that were so large that Jean Baptiste Biot called him "the richest of all the savants and the most knowledgeable of the rich".

At his death, Henry Cavendish was the largest depositor in the Bank of England.

Henry Cavendish was a shy man who was uncomfortable in society and avoided it when he could.

Henry Cavendish could speak to only one person at a time, and only if the person were known to him and male.

Henry Cavendish conversed little, always dressed in an old-fashioned suit, and developed no known deep personal attachments outside his family.

Henry Cavendish was taciturn and solitary and regarded by many as eccentric.

Henry Cavendish communicated with his female servants only by notes.

Henry Cavendish seldom missed these meetings, and was profoundly respected by his contemporaries.

Henry Cavendish enjoyed collecting fine furniture, exemplified by his purchase of a set of "ten inlaid satinwood chairs with matching cabriole legged sofa".

Theoretical physicist Dietrich Belitz concluded that in this work Henry Cavendish "got the nature of heat essentially right".