ANNUAL REPORT FOR 1875. 



87 



cement, inked with definite portions of sand, at the age of ninety days, the last eighty- 

 nine in water. 



4th. To ascertain the adhesive strength, in pounds per square inch of mortars com- 

 posed of equal parts of cement and sand, to common brick, at the expiration of seventy 

 days. 



The following table is a compilation of the average of all of my determinations, and 

 is derived from over fifteen hundred individual tests : 



The strengths of the commercial cements are derived from the average of many testa 

 of the number of brands represented below. 



For tensile strength, 14 brands of cement. 



For breaking strength, 6 brands of cement. 



For crushing strength, 11 brands of cement. 



For adhesive strength, 9 brands of cement. 



I desire to state that the average results attained by the Milwaukee product exceeded 

 the maximum attained by the best of the commercial cements. 



I have now under examination the product from a section of the Milwaukee ledge 

 extending from the surface to a depth of thirteen feet, running through eleven layers, 

 and its strength compares very favorably with the former determinations of the Milwau- 

 kee cement. 



The rock from which the cement, experimented upon, was made, was selected from 

 the banks and bed of Milwaukee river, between the west line of the east half of north- 

 west quarter of section No. 5, town 7 north, range No. 22 east, and the east and west 

 quarter line of section No. 4, same town and range. 



Yours Truly, D. J. WHITTEMORE, C. E. 



ARTESIAN WELLS. As an addition to accounts of artesian wells 

 given in previous reports, the survey is indebted to the General 

 Manager's office of the Chicago, Milwaukee & St. Paul Kailway, for 

 the following: 



MILWAUKEE, July 6, 1875. 

 DR. 0. W. WIGHT, State Geologist, 



SIR: I send you below an account of the different strata found in putting down three 

 artesian wells on our lines in this state. Yours Truly, JOHN C. GAULT. 



ARTESIAN WELL AT MILWAUKEE. 



Feet. 



Earth... 170 



Lime rock , 267 



Shale.... 165 



Second Limestone 253 



Sandstone full of water 193 



Total depth 1048 



