MONROE COUNTY. 425 
fertile as the original soil. Some of these sands require the addition of aluminous matter, to 
render them of proper consistence for retaining moisture. 
Where there are no disturbances in the surface from streams or other causes, the character 
of the soil depends much upon that of the rock beneath; but owing to such causes, we 
cannot safely depend on this criterion. The upper strata of the sandstone produce a 
sandy soil, but its character is modified by the decomposition of the shales above, which 
generally supply sufficient argillaceous matter. The marl of the sandstone formation below 
the upper strata, produces a loamy soil, in some cases approaching to clayey loam. Sometimes 
this soil is mixed with gravel or sand, and no one kind prevails over an extensive district. It 
is no uncommon occurrence to find, in the same field, sandy, clayey and gravelly soil. The 
soil on the north side of the lake ridge, for the most part, is more uniform in character than 
on the south. That on the north side requires more care and labor in the cultivation, but is 
thought to produce quite as good crops as the soil on the south side. Wheat, in some instan¬ 
ces, has been sown on these soils ten years in succession. The soil above the sandstone has 
often a brownish color, arising from the character of the rock beneath. 
The shales above the sandstone produce a clayey soil, which, however, contains a sufficient 
quantity of carbonate of lime to render it extremely fertile. The soil produced by the de¬ 
composition of the shale, north of the mountain ridge, is perhaps the most productive of any 
in the county. It is peculiarly adapted to the growth of wheat; but if tilled for a long time, and 
particularly if worked while wet, it becomes “ stiff,” and hard, like clay. 
Clays might be used, to manifest advantage, on some of the sandy soils, particularly in the 
eastern part of the county, where the same farm often contains both sand and clay. 
The soil upon the limestone is from a few inches to twenty feet in depth, of a loamy cha¬ 
racter, and very fertile throughout. The slow disintegration of the limestone affords a suffi¬ 
cient proportion of carbonate of lime; and if vegetable matter be also furnished, the soil will 
not soon be exhausted. In the southern part of the county the soil is gravelly or sandy on the 
hills, and clayey in the valleys and low grounds. It contains a large proportion of carbonate 
of lime, arising from the decomposition of fragments of slaty limestone which are distributed 
throughout. In some places we find extensive deposits of coarse gravel, with boulders. 
Clays. 
The clays of Monroe county are of that kind fit for bricks and the coarsest kinds of pot¬ 
tery. The varieties are grey, blue and brown clays : grey and blue varieties prevail along the 
lake shore ; those in the interior of the county are brownish or variegated. Every part of 
the county furnishes beds of clay of greater or less extent, but the demand for bricks has been 
limited to a few points. As many as five or six beds of clay have been wrought in the vici¬ 
nity of Rochester, from which about 2,000,000 of bricks are furnished annually. Bricks 
have been made near the village of North-Penfield, and there is an extensive deposit of clay 
on the lake shore in the north part of the town of Brighton. Bricks are made near Fairport, 
[Geol. 4th Dist.] 54 
