HELDERBERG DIVISION. 
329 
There are sixty kilns for the manufacture of cement, each of which, on an average, may 
be estimated to yield forty barrels per diem, when in operation. Most of the kilns are in 
operation as perpetual kilns, during the warmer season of the year, when the Hudson river 
is navigable. In June, 1840, it was estimated that six hundred thousand barrels of cement 
would be sent to market from those kilns during that season. It was said that five hundred 
thousand barrels were manufactured there during the previous season. The Croton water 
works, and the various government works, consume large quantities of this cement; and its 
use for various hydraulic works, and for cisterns, wet cellars, etc., cause a continually 
increasing consumption. It is shipped to all our Atlantic ports, and to the West Indies. 
White’s quarries and kilns are the most numerous, and turn off about six hundred barrels 
of cement per diem. Mr. White contracts with the quarrymen to quarry and burn the stone 
for twenty-five cents per barrel, while he furnishes the fuel, (dust anthracite from skreened 
coal,) delivered at the kilns, removes the cement to the mills, grinds and barrels it. 
The kilns are built something in the form of a high furnace, except the hearth, which has 
a sloping sole of forty to forty-five degrees from the back of the kiln to the floor of the draw¬ 
ing arch at the base. These kilns are kept in perpetual operation several months, and are 
charged like a high furnace. The dust anthracite and broken cement rock are charged, as 
usual in perpetual kilns, twice in twenty-four hours, each charge being introduced in succes¬ 
sive layers at the top of the kiln, after a quantity of cement has been hauled out from the 
sole of the kiln, into the shed next the drawing arch. About a ton of dust anthracite is used 
daily in a kiln that burns forty barrels per diem. The kilns are usually built double or triple, 
that is, two or three, or even more, are built in one stack, one set of men being sufficient to 
attend several kilns. Some have roofs over them, others have not, but all have sheds over 
the drawing arches, in consequence of the necessity of protecting the cement from the 
weather. 
At Lawrence’s works there are two blocks of kilns, one containing six kilns and the other 
seven. The quarries, kilns, mills for grinding, and barrel factory, are almost contiguous, 
and on the banks of the Delaware and Hudson canal. These works economize labor and 
transportation more than any others I have seen connected with the cement manufacture, and 
they turn off from fifteen hundred to three thousand barrels of cement per week. 
The cement business of Ulster county gives direct employment to at least seven hundred 
men, as quarrymen, burners, teamsters, millers, packers, coopers, and those engaged in 
transporting the article to New-York ; and indirectly it affords employment and profit to many 
others. 
fronts, which in their natural position in the earth were in horizontal layers, and in the buildings the planes of stratification were 
vertical. The pressure was then in a direction perpendicular to that to which they had been subjected before. It is often the 
case that these masses begin to scale off the sides and crumble away, until the structure tumbles down, or the defective masses 
are replaced by better materials. This principle is almost universally neglected in the United States. I have seen some build¬ 
ings constructed at great expense that are in a state of rapid decay from a neglect of this principle, which is recognized by every 
engineer that deserves the name, and ought to he by every architect. 
Geol. 1st Dist. 42 
