56 GEOLOGICAL REPORT. [1l95 



son to hope that they will not long remain unused. It is quite 

 likely that due S. of Eastport. and on Big Bear Creek, they may 

 be found to approach the R. R. much nearer than is the case on 

 Yellow Creek. The limestone I have seen on Little Bear Creek, 

 however, at Mr. Commons' (IF 8 1), as well as that cropping out on 

 Big Bear Creek near the crossing of the R. R.. though impure, is 

 of a different character, and probably better adapted to burning- 

 lime for agricultural purposes, than for the manufacture of 

 hydraulic cement. 



95. Limestones, for quicklime. — Most of the limes-tones mentioned 

 above (182 to 87) are suited to the manufacture of quicklime ; the 

 localities, however, where the limestone occurs in the greatest 

 abundance and purity, are at the Cypress Pond (Walnut Peak P. 

 0., 185,86), and at McDouglas' mill on Mackay's Creek waters 

 (187). At the former place, as before observed, two varieties of 

 limestone occur ; one, the uppermost stratum, being gray, and 

 rich in fossils, the lower, black and almost without shells. Both 

 rocks indiscriminately have been used in the preparation of quick- 

 lime, the product being of excellent quality, and perfectly white. 

 The upper stratum containing the shells is. nevertheless, the purer, 

 and ought to be preferred when the lime is to be employed in 

 plastering and whitewashing. An analysis of this upper, purer 

 rock, yielded the following result : 



GRAY LIMESTONE FROM THE CYPRESS POND. 



Insoluble Matter 1.680 



Lime 53.495 



Magnesia 0.817 



Peroxide of Iron and Alumina 0.580 



Carbonic Acid 42.035 



Carbonaceous Matter 1.340 



99.947 

 1 cwt. of the limestone will therefore yield 56^ lbs. of strong 

 lime, containing not quite 3 lbs. of foreign matter. This limestone 

 is, therefore, the purest found in the State, and will yield lime 

 equally as good as the majority of the imported article. 



The limestone at McDouglas' mill is somewhat variable in its 

 different ledges ; several of these are equally pure, if not purer, 

 than that of the Cypress Pond. This is especially the case with 

 those on whose fractured surfaces we see numerous smooth faces of 



