LIME AND CEMENT INDUSTEIES 769 



LrMESTO]STE OCCURRE^TCE BY COUNTIES^ 



In the following descriptions it has been attempted to give as 

 far as possible the occurrence and extent of the different lime- 

 stone formations in each county, together with their characters. 

 As many analyses as possible have been collected, and a number 

 of additional ones made for the report. Reports of an economic 

 nature are rare, but a number of county and locality reports have 

 been issued, the titles of papers and reports relating to the region 

 being given. Where the report contains analyses, it is marked with 

 an asterisk (*), and reports of an economic nature are also pre- 

 ceded by a dagger (t). 



Albany county^ 



The only limestone formations in this county are the Lower 

 Helderberg and the Corniferous. The former are specially con- 

 spicuous, as they form the Helderberg escarpment, which in this 

 county reaches its greatest elevation. 



Ono7]daga limestone. In Albany county, this formation ap- 

 pears as a terrace extending along the foot of the slopes formed 

 by the Hamilton shales. In the northeastern face of Helderberg 

 mountain the outcrop is narrow, but it widens to the w^otward, 

 being a mile and a half at Thompsons lake, and after narrowing it 

 again becomes 3 miles wide in the long slopes northwest of Berne. 

 The formation in this county is a light bluish gray, tough, mas- 



1 General articles on New York limestones 

 Hall, James. County reports, {see Geol. 4th dist. N. Y.) 

 Merrill, F. J. H. Mineral resources of New York state, {see Bui. 15. N. Y. 

 state mus.) 



Guide to the study of the geological collections, {see Bui. 19. N. Y. 



state nius.) 



Merrill, G. P. Stones for building and decoration. 



E-ies, H. Keport on limestones of eastern New York and western New Eng- 

 land, {see 17th an. rep't U. S. geol. sur., chapter on limestone) 



Smock, J. C. Building stones in Ncav York, {see Bui. 3 and 10. N. Y. 

 state mus.) 



2 Dartcn, N. H. Report on relations of Helderberg limestones in easteni 

 New York, {see 13th rep't N. Y. state geol. 1893. p. 197-228) 



Preliminary report on the geology of Albany co. (see 47th an. rep't 



N. Y. state mus. p. 425-55) 



*t Nason, F. L. Fconomic seology of Albany county, (see 13th an. rep't 

 N. Y. state geol. 1893. p. 263-87) 



Mather, W. W. Geol. 1st dist. N. Y. 1843. 



