376 ANNUAL REGISTER, 1810. 



early to pneumatic chemistry, lie 

 ascertained, in 1766, the extreme 

 levity of inflammable air, nowcail- 

 ed hydrogen gas. On this disco- 

 very many curious experiments, 

 and particularly that of aerial na- 

 vigation, have been founded. In 

 the same paths of science he made 

 the important discovery of the 

 composition of water by ihe union 

 of two airs ; and that laid the 

 foundation of the modern system 

 of chemistry, which rests princi- 

 pally on this fact, and that of the 

 decomposition of water,announced 

 soon afterwards by M. Lavoisier. 

 So many and such great discover- 

 ies spread his name througliout 

 Europe, and he was universally 

 considered as one of the first phi- 

 losophers of the age. Among the 

 labours of his latter days, is the 

 nice and difficult experiment by 

 which he determined the mean 

 density of the earth ; an element of 

 consequence in delicate calcula- 

 tions of astronomy, as well as in 

 geological inquiries. Even in the 

 last year of his life, at the advanc- 

 ed age of 77, he proposed and de- 

 scribed improvements in the man- 

 ner of dividing large astronomical 

 instruments; which, though not 

 yet executed, promise very great 

 advantages. These pursuits, toge- 

 ther with reading of various kinds, 

 by which he acquired a deep in- 

 sight into almost every topicof ge- 

 neral knowledge, formed the whole 

 occupation of his life; andwere, in 

 fact, his sole amusement. The love 

 of truth was sufficient to fill his 

 mind. From his attachment to 

 such occupations, and the constant 

 resource he found in them, toge- 

 ther with a shyness and diffidence 

 natural tohisdisposition, hishabits 

 had, from early life, been secluded. 

 His manners v ere mild, his mind 



firm, his nature benevolent and 

 complacent. He was liberal with- 

 out being profuse ; and charitable, 

 without ostentation. He possessed 

 great affluence, which was to hira 

 rather matter of embarrassment 

 than of gratification; but, however 

 careless about its improvement, he 

 was regular as to its management 

 and direction. He was born Octo- 

 ber 10, 1731, and his remains were 

 interred in the family vault in All 

 Saints, Derby. — On Saturday, 

 March 17, Mr. Professor Davy, 

 in his lecture at the Royal Insti- 

 tution, introduced the following 

 character of Mr. Cavendish. — 

 " About 1766, Mr. Cavendish 

 published his first papers on the 

 subject of air. He examined, with 

 more accurate instruments than 

 Black, the elastic fluid from the 

 alkalies; and he ascertained that 

 the same substance was produced 

 during the combustion of charcoal. 

 He perfected the pneumatic appa- 

 ratus ; and soon discovered two 

 new elastic fluids, inflammable air 

 and muriatic acid air. Mr. Davy 

 said, in the next lecture he should 

 exhibit some experiments of our 

 illustrious countryman, of later 

 date, and of still higher import- 

 ance ; but he could not, on this 

 occasion, pass by the circumstance 

 of his recent loss without a di- 

 gression, which might enable him 

 to o£Fera feeble tribute of respectto 

 the memory of so great a man. Of 

 all the philosophers of the pre- 

 sent age, Mr. Cavendish combin- 

 ed, in the highest degree, a depth 

 and extent of mathematical know- 

 ledge with delicacy and precision 

 in the methods of experimental 

 research. It might be said of 

 him, what can, perhaps, hardly 

 be said of any other person, that 

 whatever he has done has been 



