Cuvier's Biographical Memoir of M. de Lamarck. 11 



order in the Memoires de Physique et d'Histoire Naturelle,* 

 which he hastened to read to the Institute shortly after its estab- 

 lishment, and which he collected into a volume in 1797. Accord- 

 ing tb him, " matter is not homogeneous ; it consists of simple 

 principles, essentially different among themselves. The connec- 

 tion of these principles in compounds varies in intensity ; they 

 nlutually conceal each other, more or less, according as each of 

 them is more or less predominant. The principle of no com- 

 pound is ever in a natural state, but always more or less modi- 

 fied. As, however, it is not agreeable to reason that a substance 

 should have a tendency to pass from its natural condition, it 

 must be concluded, that combinations are not produced by na- 

 ture ; but that, on the contrary, she tends unceasingly to de- 

 stroy the combinations which exist, and each principle of a 

 compound body tries to disengage itself according to the de- 

 gree of its energy. From this tendency, favoured by the 

 presence of water, dissolutions result : affinities have no in- 

 fluence; and all experiments by which it is attempted to be 

 proved that water decomposes, that there are many kinds of 

 air, are mere illusions, and it is fire which produces them. 

 The element of fire-f is subject, like the others, to modifica- 

 tion, when combined. In its natural state, every where diffused, 

 and penetrating every substance, it is absolutely imperceptible ; 

 only, when it is put into vibration, it becomes the essence of 

 sound ; for air is not the vehicle of sound, as natural philoso- 

 phers believe. J But fire is fixed in a great number of bodies, 

 where it accumulates, and becomes, in its highest degree of con- 

 densation, carbonic Jire, the basis of all combustible substances, 



of certain compounds; of the colour of bodies, and of the origin of compounds 

 and of all minerals ; finally, remarks on the life of organic beings, their growth, 

 strength, decay, and death. Paris, 1794, 2 vols. 8vo. ^-ij 



• Memoirs on physics and natural history, founded on reason, independent- 

 ly of all theory, with the exposition of new considerations on the general 

 cause of dissolutions, on the substance of fire, on the colour of bodies, on the 

 formation of compounds, on the origin of minerals, and on the organization of 

 living bodies. Paris, 1797, 1 voL 8vo. 



t Memoir on the substance of Fire, considered as a chemical agent in ana- 

 lysis. Journal de Physique, Floreal an vii. 



$ Memoir on the substance of Sound. Journal de Physique, 16 & 26 Bn»- 

 maire an. vii. 



