46 MEMOIR OF LAMARCK. 



most favourite studies. So comparatively limited 

 is our positive knowledge of atmospheric pheno- 

 mena, that a careful investigation of them afforded 

 the prospect of new and important discoveries; 

 while the endless variety* of appearances which 

 they present, and the complicated influences which 

 operate in producing them, offered a wide and 

 interesting field for the exercise of that specu- 

 lative kind of inquiry which Lamarck loved to 

 indulge. With his usual facility in such matters, 

 he was not long in advancing a theory, according to 

 which the atmosphere is regarded as resembling the 

 sea, having a surface, waves, and storms ; it ought, 

 likewise, to have a flux and reflux, for the moon 

 ought to exercise the same influence upon it that it 

 does on the ocean. In the temperate and frigid 

 zones, therefore, the wind, which is only the tide of 

 the atmosphere, must depend greatly on the decli- 

 nation of the moon ; it ought to blow towards the 

 pole that is nearest to it, and advancing in that 

 direction only, in order to reach every place, travers- 

 ing dry countries or extensive seas, it ought then 

 to render the sky serene or stormy. If the influence 

 of the moon on the weather is denied, it is only 

 that it may be referred to its phases ; but its posi- 

 tion in the ecliptic is regarded as affording pro- 

 babilities much nearer the truth *. 



* On the Influence of the Moon on the Earth's Atmosphere ; 

 Journal de Physique,, Prairial, an. vi. Most of Lamarck's other 

 essays on Meteorology will be found in the periodical just 

 named. 



