288 
ANALYSES OF SOILS. 
acid, and the growth of the lower orders of vegetables, before the domesticated plants can 
be cultivated with profit upon the soil formed of it. 
The rocks passing through the wheat district are arranged in terraces more or less distinct. 
These are formed by the hard limestones and shales : the former are abrupt; the latter 
present a gradual ascent or descent. As terraces, therefore, the former are more distinct 
than the latter, and present an approach to an elevated plain, while the shale terraces appear 
in the form of rounded hills descending on all sides, so that their surfaces admit the rapid 
disappearance of the water that falls upon them, by which they are liable to gully as well 
as wash ; yet as slate is retentive of water, and its natural seams or joints are close and 
almost impervious, its slopes and summits feel a drought less than the soils resting upon 
limestone. The latter are traversed by cracks or open joints, which suffer the water to 
pass in streams, and thereby drain the surface to an injurious extent. In some instances 
limestone hills are insulated, or cut entirely off from the succeeding shales, and, if naked, 
or laid bare by denudation, would present on all sides a mural escarpment. It is easy to 
understand that in such cases the water escapes, flows out from the escarpments, and 
drains injuriously the whole tract insulated in the mode indicated above. 
An analysis of the soil reposing upon limestone gives less lime than that reposing upon 
slate. I subjoin a few examples of analysis, which go to prove the truth of the position. 
Analyses of the soils resting upon the Pentamerus limestone , at Manlius square. 
SUBSOIL EIGHT INCHES BELOW THE SURFACE. 
Water of. absorption. 1-48 
Organic matter_ 2*80 
Silicates_85*90 
Peroxide of iron and alumina_ 8*57 
Carbonate of lime. 0*21 
Magnesia. 0*05 
99-01 
This soil forms the first limestone terrace above the village, towards Chittenango. 
SURFACE SOIL. 
Water of absorption_ 2-81 
Organic matter_ 4-59 
Silicates. 84-64 
Peroxide of iron and alumina_ 7-28 
Carbonate of lime_ 0-50 
Magnesia... 0-16 
99-98 
The soil of this terrace is not supplied with a greater amount of drift than usual, and yet 
the quantity of lime is less than upon the Marcellus slate. 
