Forming Effects of Water. 37 cafe with the loweft link of the calcareous fami ly. The vaft accumulations of calc-finter found in limeftone caves, as in thofe of Derbyfhire, the Hartz, the Fichtelgebirge, Antiparos, Gibraltar, &c. belong alfo to the chemical formations. Calc- finter is found ufually in inclofed fpaces, whereas calc-tuff is formed in open fpaces. This fubftance is depofited fometimcs in caves, and frequently in in fiffures, forming veins, which are in this manner filled with very compad calc-finter, and fometimes even with cryftallized calc-fpar. Calc- tuff is formed, by calcareous brooks emptying themfelves into hollows, and thus affording an opportunity Tor the depofition of their calcareous contents. Near Canftadt in Wurtemberg, ftreams of this kind incruft every thing in their vicinity with calc-tuff, which approaches more or lefs to calc-finter. If fuch ftreams flow into fituations where the water has repofe and time to depofite its calcareous contents, calcareous beds or ftrata are formed, which are more or lefs porous. This porofity is increafed on the land, by the tuff mixing with reeds and grafs. In beds of this fubftance, fkeletons of extind quadrupeds are met with. The preceding detail affords us the following general conclufions : that precipitates are formed from the waters of the globe: that thefe are of different kinds j as calc-tuff, calc-finter, calc fpar, meadow