No. 50.] 
459 
constant greenness of the fields, and the abundant supphes of water, 
that are not to be found in many portions of the country farther north. 
Alluviums. 
In the large valleys, and generally throughout the county, the suc- 
cession of alluvial deposits is clearly defined. Resting immediately 
upon the rocky floors of the broader and more extended valleys, is a 
deposit characterized every v^rhere by the presence of materials v^hich 
have been transported from more or less distant northern localities. 
The proportions of the different ingredients are variable. Toward the 
Pennsylvania line, the olive sandstone fragments predominate greatly 
over the pebbles of limestone and primitive rocks from the north. But 
as the borders of Genesee and Erie counties are approached from the 
south, the olive sandstone pebbles are less and less frequently met 
with, until at length they are no longer seen ; and the more northern 
clays and sands, with the associated gravel, constitute the great bulk 
of the soil. This variety of soil is usually valued in proportion to the 
prevalence of these clays and gravel. Where the proportion is large, 
thirty bushels of spring wheat have been produced from an acre. 
Where, however, it is small, the attempts to cultivate wheat have uni- 
formly been unsuccessful. At Waverly, Zoar, and at Lime lake, and 
in the region about each of these localities, the alluvium which con- 
tains a large proportion of calcareous and aluminous ingredients from 
the north, prevails over all the others. 
The beds of clay, marl, tufa, bog iron and manganese, and the 
swamps, are, most of them, in the depressions of this alluvium. 
Succeeding this above, throughout the valleys that are traversed by 
streams, is a yellowish loam, chiefly composed of disintegrated sand- 
stone and shale. It has been washed down from the hill sides and 
cliffs, by rains and the melting of snows, and emptied into the streams 
which, in their overflows, spread it out upon the low lands of the val- 
leys. It is the principal soil of the Allegany valley, and of the flats 
along the Cattaraugus creek. Crops of corn and oats have been usu- 
ally grown upon this soil. Wheat has also been produced to some ex- 
tent, but it does not succeed as well as in the alluvium which partakes 
largely of the northern ingredients. 
Upon the highlands is the hardpan, which has been in progress of 
formation from the earliest emergence of the lands from the ancient 
