ANNUAL REPORT FOR 1875. 



87 



cement, mixed 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 tests 

 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 Milwaukoe 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, 

 sjid 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 hne 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 hne of section No. 4, same town and range. 



Tours Truly, D. J. Whittemoeb, C. E. 



Aetesian "Wells. — As an addition to accounts of artesian wells 

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

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



the following: 



Milwaukee, July 6, 1875. 

 Dr. p. W. Wight, State Geologist, 



Sdb: 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. 



AETESIAN WELL AT MILWAUKEE. FeCt. 



Earth 170 



Lime rock • 267 



Shale 165 



Second Limestone 2t).i 



Sandstone full of water 193 



Total depth 1048 



