AN INVESTIGATION INTO THE 
light and magnified 2 7 diameters, is shown in Plate VB. In the photomicro- 
graph a fragment of a Monticuliporid is seen in the center of the field, while 
the darker areas about the periphery of the field are Crinoid fragments, each 
with a secondary enlargement, consisting of pure calcite, surrounding it. 
Trenton Limestone, Montreal, Canada. 
No 
a 
a 
6 
6 
a 
6 
Size 
.97 
.984 
.97 
.984 
Area . 
.749 
.749 
.762 
.762 
E 
9,280,000 
9,490,000 
9,120,000 
8,930,000 
- - 
<r 
.25 
.2562 
.2545 
.2482 
D . . 
6,180,000 
6,480,000 
6,190,000 
5,820,000 
C 
3,710,000 
3,775,000 
3,645,000 
3,415,000 
Longitudinal compression. Multiply readings by 4 for millionths. 
Lateral 
extension 
(millionths). 
Load (in pounds). 
Side 
U. 
Side 
P. 
Side 
U. 
Side 
P. 
I OOO 
o 
50 
90 
140 
1 80 
225 
O 
50 
90 
135 
175 
220 
2 2O 
1 80 
143 
95 
54 

O 
50 
85 
135 
1 80 
225 
225 
190 
140 
90 
54 
4 
O 
50 
90 
I 3 
170 
230 
230 
185 
140 
95 
55 
5 

30 
60 
95 
135 
175 
O 
34 
70 
IOO 
140 
1 80 
2 OOO 
3,ooo 
4, OOO. . 
5.OOO. . . 
6 ooo 
7 OOO 
8 ooo 
9 OOO. 
8 ooo 
7,000 
6,000 
225 
185 
149 
95 
55 
4 
175 
140 
IOO 
65 
32 
2 
1 80 
147 
1 06 
73 
35 
2 
5 ooo 
4 OOO 
-i .OOO 
2,000 
I, OOO 
700O 
5000 
Q 
^3000 
J 
1000 
40 80 120 160 ZOO ^4O 
FIG. 10. Trenton limestone. Stress-strain curves. 
