30 MEMOIR OF LAMARCK. 



particularly on those of Combustion ; of the raising 

 of Water in the State of Vapour ; of the Heat pro- 

 duced by the Friction of solid Bodies against each 

 other," &c. &c. A condensed view of the opinions 

 promulgated in that work, and some others on the 

 same subject, is thus given by Cuvier. According 

 to our author, " Matter is not homogeneous; it 

 consists of simple principles, essentially different 

 among themselves. The connexion of these prin- 

 ciples in compounds varies in intensity ; they mu- 

 tually conceal each other, more or less, according as 

 each of them is more or less predominant. The 

 principle of no compound is ever in a natural state, 

 but always more or less modified : as, however, it is 

 not agreeable to reason that a substance should 

 have a tendency to depart from its natural condition, 

 it must be concluded, that combinations are not 

 produced by Nature, but that, on the contrary, she 

 tends unceasingly to destroy the combinations which 

 exist, and each principle of a compound body tries 

 to disengage itself according to the degree of its 

 energy. From this tendency, favoured by the pre- 

 sence of water, dissolutions result: affinities have 

 no influence; and all experiments by which it is 

 attempted to be proved that water decomposes, and 

 consists of many kinds of air, are mere illusions, 

 and that it is fire which produces them. The 

 element of fire* is subject, like the others, to modi- 

 fication when combined. In its natural state, every- 



* Memoir on the substance of fire, considered as a chemical 

 agent in analysis.— Journal de Physique, Floreal, An. vii. 



