‘922 THE JOURNAL OF GEOLOGY. 
ened wax and a couple of dark lines at intervals of about 34 inch 
above it. It was shoved about 12 inches, Fig. 5 (by transmit- 
ted light). 
Experiment 7.—A box 4 feet long was furnished with two 
escarpments each 7 inch high. The first extended one-half the 
Fic. 6. 
length of box and the second 14 inches from the back and lay 
upon the first. The wax was provided with a basal layer of dark 
wax and two dark lines. The shove was 18 inches. Fig. 6. 
Experiment §—The arrangement in Experiment 7 was altered 
by taking 1% inches from the upper escarpment and removing 
a piece 5 inches long from the lower, leaving a valley with an 
obstruction of 6% inches in front of it. The form of the base may 
be seen in the figure. The basal layer was substituted by a line 
at the level ofits top. The shove was 18 inches. — Fig. 7. 
Experiment 9—The last two escarpments in Experiment 8 
were removed and one of the same height and 7% inches long 
‘substituted, having a valley 10 inches long. The lines were as 
in Experiment 8. The shove was 18 inches. Fig. 8. 
Experiment ro.—The same arrangement as in Experiment 9, 
but the wax was allowed to remain at rest five minutes with its 
front in the valley between the two escarpments. Fig. 9. 
Experiment 11,—The valley was decreased to 734 inches by 
