346 
[Assembly 
The red sandstone and the indurated marl of the same formation have 
been used for building stone, but experience has proved what a know- 
ledge of their composition would have foretold , viz. that in Monroe 
county they are almost entirely unfit for any useful purpose whatever. 
Many apparently compact blocks of this rock will, in the course of a 
few weeks, if exposed, crumble into a loose mass. Where used in 
buildings, it has in some cases been little affected by the weather, but 
in most it has been rapidly destroyed. The aqueduct at Rochester, con- 
structed of this stone, has been for years in a dilapidated state, and will 
soon be entirely unfit for use. The great objection to the stone, is the 
presence of a large proportion of aluminous matter, absorbing water and 
destroying the stone by the same process that the hydraulic cement is 
removed from the walls of locks. The stone used for the aqueduct now 
being constructed, is far superior to the sandstone, but still unfit for the 
purpose. The compact portions are durable, but there are seams of ar- 
gillaceous matter, some of them scarcely perceptible, and others where 
this matter has been removed; all of these will absorb water, which, by 
expansion in freezing, will finally split the stone. The effect of freez- 
ing water on this stone, is illustrated in many of the locks in the vicinity 
of Syracuse, where every stone in which the seam occurs is split. This 
objection is a very serious one, and when a work of the magnitude of 
the Rochester aqueduct is to be constructed, more care should be ob- 
served in selecting the material. 
The limestone of Monroe county affords no marble or materials for 
decoration. The more siliceous portions of the bituminous limestone 
furnish a fine material for McAdamizing roads, and are much used near 
Rochester for that purpose. Paving stones are obtained from the dilu- 
vial hills. Flagging stone is not abundant, but is found among the sili- 
ceous strata of the gypseous rocks. 
The sandstone has been quarried near the outlet of Irondequoit creek, 
and used in the construction of piers at the mouth of the Genesee river. 
By the action of the waves and freezing water, it is very rapidly de- 
stroyed, and it becomes necessary to rebuild the piers almost annually. 
The stone from this quarry -has recently been rejected for the construc- 
tion of piers, and limestone substituted. An expense of several thou- 
sand dollars had been incurred in opening the quarry, and making the 
preparations, before the stone was rejected. Had the proprietors sub- 
mitted the stone to the examination of some competent person, or to the 
common tests, all this expense would have been saved. 
