FIELD CoLUMBIAN MusEuM 
PUBLICATION 18. 
Geological Series. Vol. 1, No. 2. 
OBSERVATIONS 
SN rOPOCATEPETL: AND 
IXTACCIHUATL 
WITH A REVIEW OF THE GEOGRAPHIC AND GEOLOGIC 
FEATURES OF THE MOUNTAINS. 
ey, 
OvIvPReO, FARRINGTON, PH.D., 
Curator, Department of Geology. 


Cuicaco, U. S. A. 
April, 1897. 
