12 Professor Macaire on the 



dore de Saussure perceived that this colour was owing to a se- 

 diment deposited by the water ; a sediment which burnt in 

 the air without odour, and left a black residuum. This he 

 collected for analysis ; and found it composed of copper, 19 ; 

 oxide of iron, 4-25 ; carbonic acid, 9 ; clay, 2 75 ; lime, 1 ; 

 silica, 33; water and inflammable matter, 31. It must be in- 

 ferred from this analysis that it is to the carbonate of copper 

 that the water owes its colour. 



The ardour of young Saussure, thus become the inseparable 

 companion of his father, and associated with him in all his 

 works, was almost too great for a man now advanced in years 

 and weakened by illness ; we accordingly find, on numerous 

 occasions noticed in the Travels among the Alps, the son con- 

 tinually asking to go higher and further, while the father re- 

 fuses, and thinks that they have gone far enough. 



At this time the fury of the revolution put an end to these 

 useful scientific travels, which Horace Benedict de Saussure 

 had continued with admirable perseverance for so long a period 

 of years. The revolutionary whirlwind having likewise swept 

 over Geneva, Theodore de Saussure, along with a considerable 

 number of individuals of his own age, was obliged to leave his 

 country for a time. He took refuge in England, along with a 

 distinguished man, Alexander Marcet, who afterwards became 

 his colleague in the college of Geneva, and gained a high repu- 

 tation in the physical sciences. After having traversed England 

 and Scotland he returned to Geneva, and resolved henceforth 

 to devote his scientific life to one object of research and labour. 

 I have mentioned that, following the impulse given to him by 

 his father, it was particularly to the chemical sciences that 

 Theodore de Saussure had directed his studies ; and these he 

 had greatly extended during his travels in France and Eng- 

 land, where chemistry was at that time cultivated with great 

 activity. This science had just undergone one of those com- 

 plete and radical revolutions which, by substituting principle 

 for principle, and theory for theory, produce the necessity, so 

 to speak, of reconstructing the whole edifice, and causing the 

 labours of our predecessors to go for nothing. At the period 

 in the life of Theodore de Saussure of which we now speak, 

 this work of reconstruction was well advanced in regard to 



