THIRD ANNUAL REPORT 
Of the fourth Geological District of the State of 
New- York, by James Hall. 
To His Excellency William H. Seward, 
Governor of the State of JSTew- York. 
SIR:— 
Conformably with a commission received under the law autho- 
rizing a Geological Survey of the State, I have the honor to submit the 
following report of the progress of the survey in the district assigned 
me. 
During the past season, the examinations in the Fourth Geological Dis- 
trict have been principally directed to the counties of Seneca, Ontario, 
Yates, Tompkins and Chemung. Some cursory observations were made 
in the county of Steuben; and a re-examination of some parts of Wayne, 
with a view to ascertain the true position and extent of the iron ore, as well 
as to determine whether it be confined to a single bed or stratum, as 
heretofore supposed. The iron ore of Wayne county is of more econo- 
mical importance than any other object, the gypsum excepted, in this 
part of the State; and I considered it necessary to devote some time to 
this subject. 
Examinations in that part of the Fourth District which embraces the 
southern range of counties, can be profitably pursued only during a 
short period of the summer months. It becomes necessary therefore to 
divide our labors between these and the more northern and cultivated 
counties, instead of exploring throughout its whole extent each indivi- 
dual group or series of rocks. This would certainly be preferable, since 
the rocks are of variable character, and some essentially change or en- 
tirely disappear farther west; and from the limited portion examined, 
we are prepared to find very great differences in the fossil contents of 
groups at distant points. Such a course however could not be obviated. 
