0 
OF NORTH AMERICA. 
115 
the State of New York, made under Legislative Authority; and the Geological Survey of Wisconsin, Iowa, 
and Minnesota, made by order of the United States Treasury Department. The survey of New York 
was accomplished between 1886 and 1842, and that of theUpper Mississippi region betweenl889 and 1851. 
When the survey of the State of New York was commenced, the Transition strata were not known 
in detail; Vanuxem considered all the stratified rocks in this State as belonging to the Transition 
epoch; and Taylor had found the Old Red Sandstone in the environs of Blossburg, Pennsylvania; 
this was the state of knowledge on that subject. The mission, then, of this survey was to make known 
the Transition strata of the New World in detail. The State of New York was divided into four 
districts; the first including the City of New York and the town of Schoharie; the second, the north- 
ern part of the State, with the villages of Potsdam and Chazy; the third, the Mohawk valley , with 
Trenton falls and Utica; and the fourth comprehending the western part of the State, with the falls 
of Seneca, Rochester, and Niagara. The four geologists appointed in 1836, were: William W. 
Mather for the first district. Professor E. Emmons for the second, T. A. Conrad for the third, and 
Lardner Vanuxem for the fourth. The FIRST ANNUAL REPORT was dated ll‘'’Febr. 1837, and in 
the part relating to the third district, by T. A. Conrad, the following divisions are found (see, 
page 158., etc.): 
Gneiss. 
1. Calcareous sandstone of the Mohawk valley, or Calcifirous sandrock of Prof. Eaton. 
2. Bastard limestone, or sparry limestone of Prof, Eaton. 
3. Gray sparry limestone of the Mohawk valley. 
4. Blue foetid limestones and shales of Trenton falls^ 
1. Gray sandstones and shales of Salmon river. 
2. Red or Variegated sandstone of Niagara river. 
[ 3. Red oxide of iron and associated strata, or ferriferous slate of Professor Eaton. 
Onondaga limestone series. 
Shales of the superior series, or pyrilifcrous rocks of Professor Eaton. 
if the first, second, and fourth districts, there is no attempt at the classification 
of strata, although it is probable Vanuxem had already classed in a series the rocks of the fourth 
district. In 1837, a change was made in the arrangements for the survey, Conrad was named 
paleontologist for the whole State , Vanuxem took charge of the third district , and was replaced in 
the fourth by James Hall, who had hitherto been employed by Professor E. Emmons as an as- 
sistant in studying the iron ores of the northern district. 
The SECOND ANNUAL REPORT, dated Albany Febr. 20”' 1838, contains in the part devoted 
to the second district, by Emmons p. 214 etc., the first description and denomination of the Potsdam 
Sandstone , where it is called Sandstone of Potsdam of S' Lawrence County. In that of the third district, 
now under the charge of Vanuxem, page 282 etc., is the following series, beginning with the 
lowest in the ascending order : 
Section 
I. 
Section 
It. 
Section 
III. 
Section 
IV. 
In the reports 
Gneiss. 
Calci/erous sandrock. 
Birdseye limesto7ie. 
Trenton limestone. 
Black shale. 
Green shale and its sandstone. 
Millstone grit. 
Protean group. 
Red shale. 
Water limes. 
Upper limestone. 
White sandstone. 
Pyriliferous rock. 
