ECONOMICAL GEOLOGY. 



Some strata of the calciferous furnish excellent 

 material for foundations and roug^h stone work, and 

 there is plenty of it, and it is cheap. The Trenton 

 and La Salle limestones make g"ood building* stone, and 

 some of the beds rock that dresses well and wears 

 at least as well as Joliet stone. None of the rocks are 

 hard enough to polish well, and it is a sad misuse 

 of terms to call them marbles. They are g-ood lime- 

 stones; that is all. Both make strong- lime, but when 

 used for plastering- it needs careful treatment or the 

 walls blister. The Trenton is reported by a hig-h 

 authority to contain 95 per cent, of pure carbonates. 



The calciferous, as is g-enerall}" known, furnishes 

 a larg-e amount of material for the manufacture of 

 water lime, hydraulic lime or cement. There are 

 extensive works for this purpose at Utica and also 

 at Pequamsaug-gin creek, two miles west of Utica. 



The St. Peters sandstone forms excellent material 

 for the manufacture of g'lass, when washed, being- free 

 from any admixture of other matter, and it is larg-ely 

 used for this purpose, producing- an article of superior 

 quality. It is also used for sanding- railway tracks on 

 g-rades and in rolling- mills and for other purposes, and 

 is extensiveh^ quarried, washed and shipped. 



