XIV . 2 Witt: Effect of Calcium Sulphate on Cement 231 
Table III . — Mill test to establish relation between sulphuric anhydride and 
setting time. 
Sample No. 
Time. 
Sulphur- 
ic anhy- 
dride. 
Normal 
consist- 
ency. 
Initial 
set. 
Final set. 
Fineness 
(200- 
mesh). 
• 
p. w. 
Per cent. 
Min. 
Min. 
1 
6.00 
2. 16 
24 
170 
270 
89.0 
2 
6.30 
2. 15 
24 
140 
270 
8 — — - 
7.00 
2.06 
24 
150 
290 
87.2 
4 _ 
7.30 
1.92 
24 
190 
270 
6 
8.00 
1.13 
65 
130 
87.8 
8. 80 
0. 96 
7 
8.46 
0.93 
flash 
8 
9.00 
0. 89 
flash 
88.9 
9 
9. 15 
0. 82 
flash 
10 
9.30 
0. 79 
ii,_. 
9.45 
0. 76 
12 
10. 00 
0.69 
89.5 
13 
10. 30 
0.62 
14 
11.00 
1. 13 
89.6 
15 — - 
11 30 
1. 44 
24 
170 
220 
a. m. 
16.. 
12.00 
1. 72 
24 
130 
230 
86.2 
17— ^ 
12.30 
1. 64 
24 
170 
230 
18... 
1.00 
1. 64 
24 
150 
280 
86.2 
Table IV . — Effect of exposing cement of various sulphuric anhydride con- 
tents to the atmosphere for different periods of time. 
Sam- 
ple. 
No. 
Test. 
Days of exposure. 
None. 
2. 
4. 
9. 
16. 
32. 
85. 
1 
Initial set 
min 
170 
200 
240 
240 
210 
300 
170 
1 
Final set 
... min_. 
270 
400 
450 
300 
600 
640 
260 
1 
Normal consistency 
24 
24 
24 
24 
25 
o3 
33 
4 
Initial set 
min 
190 
190 
250 
10 
16 
35 
100 
4 
Final set.._ 
min__ 
270 
380 
460 
150 
160 
45 
170 
4 
Normal consistency 
24 
24 
24 
24 
24 
33 
33 
6 
Initial set 
.min.. 
66 
0 
35 
3 
7 
25 
80 
6 
Final set 
min.- 
126 
0 
300 
220 
160 
36 
160 
6 
Normal consistency 
24 
24 
24 
24 
25 
33 
33 
13 
Initial set 
min. 
0 
0 
25 
260 
200 
70 
90 
13 
Final set 
min.. 
0 
0 
720 
620 
730 
(■>) 
120 
13 
Normal consistency 
24 
24 
24 
24 
29 
29 
33 
16 
Initial set 
min.. 
170 
10 
120 
10 
10 
25 
46 
15 
Final set 
min.. 
220 
350 
640 
280 
140 
40 
170 
15 
Normal consistency 
24 
24 
24 
24 
24 
29 
33 
16 
Initial set 
min_. 
130 
140 
270 
10 
10 
15 
65 
16 
Final set. . 
.min. 
230 
350 
250 
160 
160 
30 
120 
16 
Normal consistency 
24 
24 
24 
24 
24 
29 
S3 
17 
Initial set 
min . 
170 
125 
190 
5 
5 
15 
60 
17 
Final set 
_ - min 
230 
330 
330 
200 
100 
30 
140 
17 
Normal consistency 
24 
24 
24 
24 
24 
29 
33 
“ Time of set indefinite but more than twenty-four hours. 
