French National Institute, 373 



quarter, and it will soon be submitted to the public. Guy- 

 ton has obtained the most gratifying reward that a philoso- 

 pher can expect for his researches : it was in a great measure 

 by the processes he has pointed out, viz. fumigations with 

 the muriatic acid, that the epidemical disease which ravaged 

 Andalusia was destroyed. This fact appears from the report 

 made to the Spanish government by Dr. Queralto, sent from 

 Seville for that purpose, and the report communicated to 

 Guyton by M. Gimbernat, one of the pensioned travellers of 

 the king of Spain. 



Extraction of Soda from Marine Salt, — Berthollet has been 

 employed on a subject of great importance to the arts, the 

 decomposition of marine salt. Leblanc having published a 

 process for extracting the soda, Berthollet has made some 

 changes in it which render it more advantageous, easier, and 

 appKcable with more oeconomy to the different arts in which 

 the oxygenated muriatic acid is used. 



On the supposed Returns of the principal Variations of the 

 Atmosphere, — To be able to foretel the variations of the at- 

 mosphere would be a thing of so much general utility, that it 

 needs excite little astonishment that it should, at all times, 

 have been an object 'of research to philosophers; and it ought 

 to excite less, that the obscurity in which this as well as 

 every other part of futurity is involved, has made those who 

 pretend to foresee the variations of the air to be ranked in 

 the same class as those who prstehd to foretel moral and 

 political changes. It may, however, be easily seen that these 

 events are not of the same order ; that the causes of the 

 former are much less varied, and consequently are susceptible 

 of combinations less numerous; that these causes have not 

 the mobiiity of the affections of the mind; and that, if some 

 of them still escape us, it is not necessary they should do so 

 always. 



These reflections induced Lamarck to examine the follow- 

 ing question : — " Among the different variations of the state 

 of the atmosphere, and especially those observed in our la- 

 titudes from 40 degrees to the poles, are there any the perio- 

 dical return of which can be determined ?" Lamarck has been 

 able to convince himself that the solutionof this question can- 

 not 



