MEMOIR OF LAMARCK. 29 



to instruct others, and ultimately to produce works 

 which will form a lasting monument to his fame. 



Before engaging in the study of practical zoology, 

 Lamarck had rendered himself conspicuous hy the 

 boldness and originality of his speculations regarding 

 a variety of physical phenomena. The general laws 

 of chemistry, the origin of the globe and its inhabi- 

 tants, the condition of the atmosphere and of living 

 bodies, and most other great questions fitted to 

 attract an active fancy, had by turns been the 

 subjects of his contemplation; and on many of 

 them he had elaborated a theory which he conceived 

 calculated to elucidate the most abstruse phenomena 

 they presented. To these views he attached the 

 highest importance, considering them destined to 

 place almost every branch of knowledge on a new 

 and secure foundation. He therefore took advan- 

 tage of every opportunity to enforce and illustrate 

 them, and they will be found to pervade most of 

 his published works, even such as afford no obvious 

 plea for their introduction. Although most of 

 them are exploded as fanciful and untenable, these 

 theories display much ingenuity and extensive know- 

 ledge, and a pretty full account of them is necessary 

 to show the character of Lamarck's mind, and the 

 wide range of his studies. 



As early as 1780, he had presented his Theory of 

 Chemistry to the Academy of Sciences ; but it was 

 not published for several years afterwards, when it 

 appeared under the title of " Researches on the 

 Causes of the most important physical Facts, and 



