141 



verns, we find all the characters of a chemical 

 precipitate. The carbonat of lime has not been 

 held in suspension ; it has been actually dis- 

 solved. I am aware, that, in the experiments 

 of our laboratories, this substance appears solu- 

 ble only in water strongly impregnated with 

 - carbonic acid : but the phenomena, which na- 

 ture daily presents in caverns and springs, are 

 sufficient proofs, that a small quantity of car- 

 bonic acid is sufficient to give water, after long 

 contact, the power of dissolving some portion of 

 carbonat of lime. 



As we approach those periods, in which orga- 

 nic life displays itself in a greater number of 

 forms, the phenomenon of grottoes becomes 

 more frequent. There exist several under the 

 name of baumen*, not in the ancient sand- 

 stone, to which the great coal formation belongs, 

 but in the Alpine limestone, and in the Jura 

 limestone, which is often only the superiour 

 part of the Alpine formation. The Jura lime- 

 stone so abounds with caverns*}- in both conti- 



* In the dialect of the German Swiss, Balmen. The 

 Baumen of the Sentis, of the Mole, and of the Beatenberg^ 

 on the borders of the lake of Thun, belong to the Alpine 

 limestone. 



+ I shall mention only the grottoes of Boudry, Motiers- 

 Travers, and Valorbe, in the Jura ; the grotto of Balme 

 near Geneva ; the caverns between Muggendorf and Gailen- 

 ruth in Franconia j Sowia Jama, Ogrodzimiec, and Wlodo- 

 wice, in Poland, 



