No. 275.J 31 
46. The Manlius water limestone has the following composition: 
Carbonic acid, » 39 . 80 
Lime, - 25.24 
Magnesia, 18.80 
Silica and alumina, 13 .50 
Oxide of iron, 1.25 
Moisture and loss, * 1.41 
100.00 
47. According to Mr. Hall the formations from which water limestone 
has been selected, extend across Monroe county from east to west: the One 
through the towns of Penfield, Brighton, Gates, Ogden and Sweden; 
the other through Mendon, Rush and Wheatland. At one locality in 
Ogden this limestone has been burned and used for cement in the locks 
on the Erie canal, and is said to have been of good quality. The same 
kind of stone may be found at the upper falls of the Genesee, at Ro- 
chester.* 
In Orleans county, some of the upper layers of the rock at the falls 
of Oak Orchard creek, at Shelby, are also used for the manufacture of 
water cement. 
48. Finally, the same limestone occurs near Waddington, in St. 
Lawrence county, and is probably continuous with the stratum found 
near Kingston in Upper Canada, which is used in the public works and 
is highly esteemed.! 
Such are some of the most important localities of this valuable mine- 
ral product. The number of these will no doubt hereafter be much in- 
creased, and perhaps many quarries, now little valued, will be found 
upon examination and trial to furnish cements equal to those at present 
so generally employed. It cannot be too often repeated, however, that 
a detailed and careful series of experiments should be made before a ce- 
ment, from whatever locality obtained, is Used in important works. 
Gypsum, Plaster of Paris, or Sulphate op Lime. 
49. This important article, for which until within a few years past we 
Were almost entirely indebted to Nova Scotia, may now be ranked 
among the great mineral products of our State. 
* Prof. Hall's report for 1838. 
t The value of the water lime manufactured in St. Lawrence and exported to Canada, is 
said to be $40,000 annually. See Report of the St. Lawrence rail-road committee, December^ 
1838. 
