SWNT CHOILOCISIE, 361 
The specific heat of Portland cement, clinker was found by Dr. 
Hart to be 0.19. The heat of hydration of a number of commercial 
Portland cements in excess of water was found to be not more than 8 
calories per gram. In regard to the heat of solution of cements in acid, 
and other data, Meyer has worked out the following results. In this 
work he employed three cements of the following composition : 
Silica. Alumina. Ferric Lime. Magnesia. 
Oxide. 
Per cent. | Per cent. | Per cent. | Per cent. | Per cent. 
GOR ase 3 NA DN OS Dy 
Si eatoene D1 9.7 Bie | 6B.8 2.4 
Cee ans 20.9 8.8 DD | CRB | Be 
These cements were burnt at different temperatures and tested for 
specific gravity, alkalinity, constancy in volume and heat of solution. 
a: st ate Bee ee 
2 ee Ss 
$ Be ROSE 5 | GE | 3 7 28 90 
A | 12 13.243) 6.6 | friable | 447 0.060 0.100 0.320 0.440 
do | 1% | 3a80) 6.0 de “442 0.010 0.020 0.100 0.100 
do) 18 |e) 26) we | 447 | 0.025 | 0.050 | 0.120 | 0.180 
do} 21 |3.159! 5.6 | hard "458 0.010 0.010 0.010 0,025 
® | 29 lean Fe | rae "470 | 0.010 | 0.025 | 0.065 | 0.125 
do| 15> |3.199| 6.5 | hard 440 | 0.005 | 0.015 0.045 0.050 
do| 18 |3.195| 4.4 | good 471 | 0.015 | 0.020 | 0.035 | 0.035 
alo |. Zl 3.160 5.1 | good Lf BAD | ba oe | Se pepae cleat | 0.015 
G 2, | Do IGS | JU. I | broke down | 525 | 0.040 | 0.090 | 0.500 | 1.520 
do} 15 | 3.200! 9.6! brokedown | 577 | 0.025 | 0.060 | 0.150 ; 0.420 
do| 18 | 3.230, 8.6} very friable | 542 0.060 0.100 | 0.250) 0.450. 
do} 21 |3170| 7.0 | very friable | 517 | 0.125 | 0.125 0.420 | 0.850 
The “alkalinity” means the number of ce. of deci-normal acid used in 
neutralizing 50 cc. of distilled water which was in contact with 0.5 gram 
of cement. . 
