REPORE OF COMMITTEE ON PHOTOGRAPHS. 419 
The attention of members desiring prints is called to the fact that ap- 
plication for the same should always be made to the holder of the neg- 
atives and not to the chairman of the committee. 
The committee ask a continuation of the appropriation of $15.00 for 
expenses during 1898, and an additional appropriation of $35.00, or such 
part thereof as may be needed, to be used in preparing prints from the 
series of negatives received from the Second Geological Survey of Penn- 
sylvania. 
Respectfully submitted. GEORGE P. MERRILL, 
Chairman. 
Wasuineron, December, 1897. 
REGISTER OF PHOTOGRAPHS RECEIVED IN 1897 
Fourteen views photographed by Dr O. C. Farrington and presented by Field Columbian 
Museum, Chicago, 1897 
Size, 43 by 63 inches. Figures in parentheses are original numbers 
1422 (1). Till or boulder-clay, section K, Chicago drainage canal. 
1432 (2). Drift, section 5, Chicago drainage canal. Shows sudden transition 
from coarse drift to fine sand; also highly inclined bedding. 
1424 (3). Drift, section 5, Chicago drainage canal. 200 feet below number 2. 
Drift very coarse; boulders are limestone. 
1425 (4). Kame, section 10, Chicago drainage canal. 
1426 (5). Section of kame shown in number 4, showing drift. 
1427 (6). Drift on limestone, section 7, Chicago drainage canal. Bedding of 
both drift and limestone horizontal. Drift channeled by streams. 
1428 (7). Drift on limestone, section 6, Chicago drainage canal. The upper 
surface of the limestone is broken and shattered at the contact with 
the drift apparently by resistance to glacial movement. The resist- 
ance was also unequal, part of the limestone near the contact at the 
right having been entirely carried away. The direction of glacial 
movement was from left to right. 
1429 (8). ‘‘Clay pocket,” section 7, Chicago drainage canal. The limestone has 
undergone differential internal disintegration, causing portions of 
the strata to falland become tilted. The section is 36 feet in height. 
1430 (9). ‘‘Clay pocket,” section 10, Chicago drainage canal. The hollow 
formed in the limestone by disintegration has been filled from above 
by drift. 
1431 (10). Postglacial erosion of limestone cliff, near Lamont, Illinois. 
1431 (11). Nearer view of number 10. 
Views in Mexico 
1433 (12). Porfirio Diaz glacier, Ixtaccihuatl, Mexico. From the old terminal 
moraine. 
1434 (13), Weathering of quartz vein, near El Bote Mine, Zacatecas, Mexico. 
The surrounding rock is chlorite schist, : 
