No. 275.J 
27 
The lime thus calcined, is of a light drab colour, and when reduced to 
powder and mixed with about one-third its bulk of sand and made into 
paste with water, soon becomes hard. The grinding is performed in a 
mill, and the powdered cement is put up in barrels, which are lined with 
paper, to exclude as much as possible, the contact of air. The cement 
thus prepared, is sold at $2.25 the barrel. 
It is estimated that about 3,000 barrels of cement are manufactured 
in this district, weekly. Supposing this to be continued for only six 
months in the year, the income arising from it will amount to nearly 
$150,000. As an evidence of the good quality of this cement, it may 
be stated, that it is employed in the construction of the Croton aqueduct 
and in the United States works, near Boston. 
37. I analyzed a specimen of this hydraulic limestone, or cement, as 
it is sometimes called, from the quarry of Messrs. Moser & Burnett. 
It had a blueish colour, with occasional gray and reddish spots. The tex- 
ture was close and compact, and its fracture even or conchoidal. The 
following are the results which were obtained in 100 parts. 
Carbonic acid, 34.20 
Lime, 25.50 
Magnesia, 12.35 
Silica, 15.37 
Alumina, 9.13 
Oxide of iron, 2.25 
Bituminous matter, moisture and loss, , 1 .20 
100.00 
The calcined cement contained only five per cent of carbonic acid, 
and its composition may be thus expressed. 
Carbonic acid, 6.00 
Lime, 37.60 
Magnesia, . 16 . 65 
Silica, 22.75 
Alumina, 13.40 
Oxide of iron, 3.30 
Loss, , 1.30 
100.00 
