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First edition, complete journal volume, of the discovery of hydrogen. "One of the first publications by Cavendish, titled 'Three papers, containing Experiments on factitious Air', appeared in the journal Philosophical Transactions in 1766 . . . By 'factitious air' Cavendish meant 'any kind of air which is contained in other bodies in an inelastic state, and is produced from thence by art'. The term had originally been introduced by Boyle. The first paper was on Inflammable air, which we know today as hydrogen. Other investigators such as Boyle had previously prepared this gas but had not realized what it was. The detailed studies of Cavendish allowed him to be credited as the first person to recognize its true nature. Cavendish prepared the gas by the action of acids on various metals. The two acids that he used were spirit of salt (hydrochloric acid) and dilute oil of vitriol (sulfuric acid). He studied three metals: zinc, iron, and tin. Various types of apparatus were used in his experiments and these are illustrated in his publication [plate VII*]. Cavendish described inflammable air as permanently elastic, which was a term used to describe all gases at the time. He showed that the volume remained constant despite the gas being exposed to water or alkalis. In fact it was so insoluble in water that there was no measurable absorption over a period of several weeks. Finally he described that it was explosive when it was mixed with common air and exposed to a spark, and he noted that this behavior had been described by others . . . An important determination was the density of the new gas . . . Cavendish measured the density of several samples of hydrogen and compared the density with that of common air and water. He reported that the mean density was 8700 times lighter than water. This meant that it was much lighter than air . . . The second of the three papers was read by Cavendish on November 6, 1766 and was about his work on 'Fixed air'. We now know this as carbon dioxide and it had previously been produced by Joseph Black although his description was brief. Cavendish produced fixed air by the same methods as used by Black, that is by adding acid to alkalis such as calcium carbonate or magnesium carbonate, or heating these substances, that is what is known as calcination. Cavendish explored the properties of this gas using the same techniques as he had for inflammable air. He reported that it was permanently elastic like inflammable air but in other respects it was different. First, it was soluble in water, and for that reason he collected it over mercury. He also found that it was not flammable and he reported its density as 511 times lighter than water, or 1.57 times heavier than common air. Cavendish's third paper presented to the Society on November 13 dealt with the gases produced by fermentation and putrefaction. The results showed considerable variability as we might expect and these studies are of less interest. Cavendish's work on factitious airs earned him the Copley Medal of the Royal Society, its highest distinction" (West, 'Henry Cavendish (1731-1810): hydrogen, carbon dioxide, water, and weighing the world,' American Journal of Physiology, 2014). 4to, pp. xi, 329, [1, blank], [2, ads], 17 plates (numbered I-VII, VII*, VIII-XII, XII*, XIII-XV). Contemporary calf, spine gilt with lettering piece (rubbed, joints cracked but firm). N° de réf. du vendeur ABE-1606945952869
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