NOTES OX HYDRAULIC LIME AND CEMENT. — MASON. 183 



some time after the lime had been burnt and after it had taken 



np a certain amount of carbonic acid. 

 Tlie following are the analyses : — 



Lime , 78.80 80.70 



Silica 12.20 11.00 



Alumina 1.74 1.76 



Ferric oxide 1.56 1.14 



Magnesia 48 .53 



Test pieces were made, and while they would not set under 

 water, they set in two days in a covered jar over water and 

 continued to harden under water. When thoroughly hard they 

 were put out on the window sill of the laboratory and remained 

 there the wdiole winter without in the slightest decree sufterino; 

 from the continual freezing and thawing to which they were 

 subjected. In the spring they had obtained a hardness almost 

 equal to Portland cement similarly treited. 



This was so encouraging that the writer interested other per- 

 sons, and as soon as the hand diamond-drill was available four 

 bore-hole^ were put down, three to a depth of 50 feet and one 

 to 70 feet. 



It was intended that eight holes should have been put down, 

 but owing to the severity of the past winter and the difficulty of 

 keeping the drill from freezing, only about half that amount of 

 boring was accomplished. 



The following are the analyses of average samples of each 

 core after burning : — 



1. 2. 3. 4. 



Silica 11.45 9.25 11.80 11.20 



Alumina 3.57 3.25 3.19 3.11 



Ferric oxide 1.48 1.14 1.28 1.29 



Manganese oxides 0.08 0.10 0.63 0.70 



Magnesia 0.25 0.25 0.43 0.52 



Lime 81.25 83.55 79.60 80.00 



Sulphuric oxide 0.44 0.42 1.61 1.71 



Not determined and loss .. . 1.58 2.04 1.42 1.47 



