136 Agriculture of JVew York. [Sept., 



phosphates, especially where those rocks were extensive. We 

 have ascertained that both alkalies and phosphates pervade the 

 Taconic slates. The following analyses we extract as instances 

 showing the results we have obtained. 



Analysis of 100 grs. Hoosick Roofing Slate. 



Water, 3.79 



Silicates, 70.55 



Alumina and peroxide of iron, - 20.35 



Carbonate of lime, .... 0.99 



Potash, 3.52 



Carb. mairnesia, 0.49 



Soluble silica, ..... trace 



Phosphates, ..... trace 



Analysis of a Crystallized Slate from Salem, Wash. Co. 



Water, 2.62 



Silicates, 84.65 



Alumina and peroxide of iron, - - 11.53 



Carbonate of lime, .... 0.60 



Potash, 0.60 



Soluble silica, ..... trace 



Phosphates, trace 



Analysis of a Slate similar to the above, and belonging to the 

 same System, from Waterville, Me. 



Water, 3.42 



Silica, 71.62 



Alumina and peroxide of iron, - - 23.25 

 Carbonate of lime, - - - - 0.10 



Potash, Ir52 



Carb. mairnesia, ..... 0.05 

 Soluble silica, .... trace 

 Phosphates, 0.90 



The foregoing slates are distributed over a wide area, and from 

 their composition we can see how it happens that their debris 

 supplies both phosphates and potash to the soil. These lands 

 usually produce excellent corn or maize. 



The marls in many instances will be found valuable fertilizers, 

 as may be inferred from their composition. One from Christian 

 Hollow, Onondaga county, gave the following results. 



Analysis of Onondaga County Marl. 



Gr<Tanic matter, .... 3.01 

 Water (dried at 212°) ... - 5.68 



