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I Assembly 
In the first or lowest deposit, the red shale, we have the red oxide of 
iron, the least soluble material which characterizes the group. In the 
second and third deposit, we have the gypsum, which is next in order 
as to difficulty of solution; between the two upper ranges of this sub- 
stance, we find the common salt or its hopper cavities where obviously 
it should be; and lastly the sulphate of magnesia, the most soluble of 
the four products, appears only in the terminal deposit. 
Those who wish to see a practical illustration of the order in which 
the characteristics of the group separate from each other, will find it on 
visiting the salt pans where evaporation is carried on by solar heat. 
There he will find that the first deposit is the red oxide of iron, the 
second the gypsum, the third the common salt in its form of hoppers, 
or reversed pyramids, composed of little cubes, and on enquiry he 
will learn that the magnesia salt remains in solution. 
We would also recommend a visit to Mr. Green's salt pans at Salina, 
where the boiling of brine is carried on in close vessels. There will be 
seen many products as to form, which are occasionally met with in the 
New-York rocks, and to which I have ascribed a thermal origin, such 
as oolite varying from the finest to the largest as in pisolite; also con- 
cretions of other kinds, fragments formed of thin layers that have been 
broken up and cemented together like to those we find iH portions of 
the lower layers of the "calciferous sandrock," and also in the concre- 
tionary limestone which forms the base of the saliferous group. 
Water Lime. 
The w^ater lime group of Manlius, is the next series as to age; it rests 
upon the saliferous group, and in all cases where a regular denudation 
has taken place, it is only to be found south of the gypseous range, 
being the overlying mass. The group is exceedingly well characterized 
by its fossils, of which some are extremely numerous, and are found 
from the Hudson to Cayuga lake. With but one exception, the whole 
of the water lime which is burnt for cement in Madison, Onondaga and 
Cayuga, is from this group; and the greater part of the limestone which 
is converted into lime along the same range, is obtained from it. 
With this group, all the drab or light yellowish coloured limestones 
so common, and which gives character to the group below it cease, and 
with it is the beginning of the usual kinds of blue, gray and black lime- 
stone, which exist so abundantly above, and whose range is so extensive 
east and west 
