368 
[Assembly 
Quick-lime and Hydraulic Cement, 
The geodiferous, or bituminous limestone, is the only rock in Niaga- 
ra county from which quick-lime is made. The lower portions, only, 
of this limestone, near its outcropping edge, are used for making pure 
lime; any part of it, however, is pure enough to make lime for agricul- 
tural purposes. In Monroe county, the upper strata of the same lime- 
stone are used for quick-lime, while the lower strata are unfit for that 
purpose. In Niagara county the upper strata contain much magnesia, 
and the rock is said to be unfit for making quick-lime. 
It has already been stated that the outcropping edge of this lime- 
stone follows the course of the mountain ridge, so tk.t at a glance one 
may perceive in what part of the county lime is manufactured. 
I do not know that hydraulic cement has been made in any part of 
this county, though the rock extends entirely across it. In many places 
farther east the upper strata of the calcareous shale in the mountain 
ridge, furnish the hydraulic cement used on the canal. That furnished 
for the aqueduct at Medina was from this rock, which occurs at Shel- 
by, two miles south of Medina. The cement in this aqueduct has re- 
mained more firm than any I have seen on the canal. The same strata 
extends across the county from near Middleport to Lewiston. At many 
places along this distance a good cement may be obtained, but far the 
best stone for this purpose is near the top of the ridge at Lewiston. 
The stone at this place is a siliceous limestone, with very little argilla- 
ceous matter, and containing a small proportion of the oxide of manga- 
nese. Owing to this metal the stone presents a greenish hue when first 
exposed, but finally becomes a rusty gray. 
The subject of cements for the public works of New- York, is one of 
great importance. The substance used for that purpose is, in many cases,, 
entirely unfit, and from this cause alone much loss is sustained. I do 
not hesitate to say, that the substance called hydraulic cement, in many 
cases where used, is far inferior to common mortar made with good 
quick-lime. It is to be hoped that some attention will be given to this 
subject, in the construction of the new locks and aqueducts on the Erie 
canal. 
JMaterials for Construction. 
Both the limestone and sandstone formations furnish good and durable 
materials for purposes of construction. There is a stratum of the 
sandstone formation about twenty-five feet thick, which affords a very 
fine building stone, and from the peculiar smoothness of some of the 
