158 LAMARCK, HIS LIFE AND WORK 



Only the closing years of the century witnessed 

 the rise of the experimental methods in physics and 

 chemistry, owing to the brilliant work of Priestley 

 and of Lavoisier. The foundations of general physi- 

 ology had been laid by Haller,* those of embryology 

 to a partial extent by Wolff,t Von Baer's work not 

 appearing until 1829, the year in which Lamarck died. 



Spontaneous Generation. — Lamarck's views on spon- 

 taneous generation are stated in his Recherches sur 

 I 'Organisation des Corps vivans (1802). He begins 

 by referring to his statement in a previous work;]: 

 that life may be suspended for a time and then go 

 on again. 



" Here I would remark it (life) can be produced 

 {pr^pare'e) both by an organic act and by nature her- 

 self, without any act of this kind, in such a way that 

 certain bodies without possessing life can be prepared 

 to receive it, by an impression which indicates in these 

 bodies the first traces of organization." 



We will not enter upon an exposition of his views 

 on the nature of sexual generation and of fecunda- 

 tion, the character of his vapeur subtile {aura vitalis) 

 which he supposes to take an active part in the act of 

 fertilization, because the notion is quite as objection- 

 able as that of the vital force which he rejects. He 

 goes on to say, however, that we cannot penetrate 

 farther into the wonderful mystery of fecundation, but 

 the opinions he expresses lead to the view that " nature 



* Elementa physiohgiae corporis humani, iv. Lausanne, 1762. 



f Theoria generationis, 1774. 



X Me'moires de Physique (1797), p. 250. 



