« 



791 [AssEMBLr 



•' No. 51 , if iu quantities sufficiently large, and uniform in com- 

 position, like the sample alialysed, will prove a highly valuable 

 deposit for the manufacture of hydraulic cement. In composi- 

 tion it has all the materiala present in the requisite proportions 

 for yielding a superior cement. No. 30, although a hydraulic 

 eement, yet the sample analysed is too silicious for forming a 

 sti-ong cement.'^ 



PainC exists In different sections of the county, in numerous 

 de]x>3its and various colors It is generally disintegrated and 

 pulverized, and is used in its crude state for ordinary painting. 

 When prepared by artificial refinement, it is believed the-se mine- 

 rals will be made useful for practical purposes. An ore occurs 

 in Ticonderoga of a rocky consistence which presents a bright 

 rich Vermillion surface, and it is supix>sed will yield an import- 

 ant paint. It exhibits the following components on an analysis 

 hj Prof. Salisbury. Dried at 212 degrees, 100 parts gave of 



Seequioxide of iron, 88 . 20 



Silica, 10.05 



Alumina, . 60 



Carbonate of lime, . 65 



Magnesia, 0.41 



99.91 



^* Thiii rock contains beeides the bodies mentioned above, a very 

 small percentage of manganese. I see no reason why this ore 

 might not he valuable for smelting if it occurs in suflicient quan- 

 tities. It will make a very good dull red or reddish brown paint, 

 if it can be ground sufficiently fine." 



I selected from the numerous deposits of paint in the county a 

 sample i>om a bed upon the premises of Mr. Robert Cook, of 

 Chesterfield, which I considered to possess qualities of peculiar 

 excellence. The bed lies in a ravine, in an open pasture and is 

 of easy access. The paint appears upon the surface or by the re- 

 moval of a few inches of turf, and is revealed over an area of 

 many rod5, exhibiting evidences of a vast deposit. The follow- 



