CHAP. VI., 3.] HEAT (ATOMIC CHEMISTRY). DALTON GAY-LUSSAC. 



141 



early as 1816, elected a coi-responding member of the 

 Institute of France Wollaston being then probably 

 the only other English name on the list. 1 Dalton 

 found his way to Paris in 1822, and was agreeably 

 surprised by the distinction with, which he was re- 

 ceived by the most eminent members of the Academy 

 of Sciences. Perhaps this first personal recognition 

 of his exalted station, as a man of science, had some- 

 thing to do with the tardy adjudication to him four 

 years later of one of the medals of the Royal Society 

 of London. In 1830 he was elected one of the eight 

 associates of the Academy of Sciences iu the room of 

 Sir Humphry Davy. 



(628.) In 1833, at the age of sixty-seven, he received a 

 charac- p ens i on from government, up to which time he had 

 maintained himself in the way already mentioned, 

 with the utmost simplicity and contentment. Even 

 in his lifetime it was impossible for his eulogists 

 to forbear from some reference to this essential part 

 of his really philosophic character. " Mr Dalton 

 has been labouring," says Sir Humphry Davy, " for 

 more than a quarter of a century with the most dis- 

 interested views. With the greatest modesty and 

 simplicity of character, he has remained in the ob- 

 scurity of the country, neither asking for approba- 

 tion, nor offering himself as an object of applause." 

 "There is little doubt," says Dr Thomson, "that 

 Mr Dalton, had he so chosen it, might, in point of 

 pecuniary circumstances, have exhibited a much more 

 brilliant figure. But he has displayed a much more 

 noble mind by the career which he has chosen ; 

 equally regardless of riches as the most celebrated 

 sages of antiquity, and as much respected and be- 

 loved by his friends, even in the rich commercial 

 town of Manchester, as if he were one of the greatest 

 and most influential men in the country." All who 

 had the good fortune to know him personally to see 

 him, as the writer of these pages has done, in his 

 modest school-room, and surrounded by his unpre- 

 tending apparatus will own that these eulogies are 



md death, not overdrawn. His latter days were spent in cheer- 

 fulness and comfort ; he expired on 27th July 1844, 

 having nearly completed his seventy-eighth year. 

 (629.) The philosophical character of Dalton may be 



Dalton 's briefly summed up. He had immense vigour of con- 



philosophi- , J j - i , TT 



ml charac- ception, and an ardent love ot truth. He was tho- 

 ;er. roughly devoted to the pursuit of science during his 



long career, and he evidently sought and expected 

 no higher reward than the insight which he obtained 

 into the laws of nature. His mind, like his frame, 

 was of a strongly masculine character, and happily 

 exempt from nervous sensibility and other like in- 

 firmities of genius. Whilst he held his own opinions 

 with tenacity, and criticised freely those of his op- 

 ponents, there is not a trace of acrimony in any 



of his writings ; and he always spoke in terms of 

 high respect both of those who pursued science in a 

 similar direction with himself, and (what was more 

 difficult) likewise of those who, having the good for- 

 tune to hold more conspicuous positions, showed him 

 the smallest degree of kindness, which he always 

 gratefully acknowledged. He was unlike Black and 

 Cavendish, in the rapidity with which he seized on a 

 few isolated facts, and made them the basis of an 

 inference of great generality ; this, indeed, was his 

 leading characteristic; and he differed from them 

 equally in the boldness with which he claimed from 

 the public a general acceptance of his conclusions. 

 Some of his inferences were unguarded enough, and 

 have not been confirmed ; and the reception of what 

 were correct was naturally delayed by the evident 

 facility with which his theories were shaped in his 

 own mind. Most of his papers appeared in rapid 

 succession ; only the Atomic Theory was brought 

 with some evident hesitation before the world. In 

 all this we see the results of a vigorous imagination, 

 united with great perseverance, in working out an 

 idea. The imaginative element would have been 

 more under control had his education been of a less 

 irregular kind. We see the effect of an opposite 

 turn in his eminent predecessors just named. They 

 would have done more, had they trusted more. Dai- 

 ton's discoveries may be said to have terminated at 

 the age of forty. Though he laboured for thirty 

 years after, the conceptive faculty seems to have 

 spent itself in its earlier efforts. 



JOSEPH Louis GAY-LUSSAC, an eminent French , 630 -, 

 chemist and physicist, contemporary with Dalton, Gay-Lus- 

 has been mentioned in the course of the present sec- sac cne 

 tion, as having discovered independently the equal m / st . a ?^ 

 dilatation of the gases, and also a law of their com- 

 binations in connection with their volumes, which 

 was peculiar to himself. Besides these researches, 

 science owes many useful observations in physics to 

 his energy and talent, which, in the origin of his 

 career, promised more of originality than his ma- 

 turer life perfectly fulfilled. He was born in the old 

 province of Limousin in 1778, and became the pupil 

 of Berthollet in chemical researches, and was one of 

 the earliest and most active members of the Societe 

 d'Arceuil. In physics, he was the collaborator of 

 MM. Biot, Humboldt, and Laplace. With the first R eraar k. 

 of these philosophers he made his earliest experi- able bal- 

 ment in aerostation, which he repeated alone on the loon ascent. 

 16th September 1804, when he attained the amaz- 

 ing height of 7016 metres (23,019 English feet), an 

 elevation previously unattained, and which in the 

 course of the succeeding half century has only twice 

 been touched, or exceeded by a small quantity. 2 Con- 



1 So stated by Dalton himself (Life by Dr Henry, p. 163) ; but I suspect some misapprehension. Considering the importance 

 attached to these nominations, it is to be regretted that it is at all times difficult to ascertain who are, or have been, associates 

 and correspondents of the Academy of Sciences. 



8 Once by MM. Bixio and Barral in 1850, and once by Mr John Welsh in 1852. Since this passage was written I find it 

 stated, that, on the 10th September 1838, Mr Green and Mr Kush reached a height of 27,148 feet. See The Times of 15th Sept. 

 1838. 



