No. 275.] 
35 
countries are necessary to the success of the agriculturist. Still it can- 
not be doubted that in many situations even here, much advantage 
would be derived from the use of these efficient fertilizers. Lime, marl 
and gypsum, all of which can be so easily and so abundantly obtained 
in the region in question, have almost entirely changed the agricultural 
character of the States of New- Jersey and Pennsylvania; but it appears 
to me that in no part of our State which I have visited, is the value of 
these articles duly appreciated. 
It may not be out of place here to offer a few remarks concerning 
the origin of gypsum. 
68. From the uniformly regular appearance which the beds of gyp- 
sum present throughout the western counties, the similarity in their 
geological associations, and the apparent heaving up of the strata which 
enclose them, it has been inferred that they are the result of agencies 
now in operation. The opinion indeed prevails quite generally among 
the inhabitants of the districts where plaster beds are of most frequent 
occurrence, that they increase from year to year, and that it is unsafe 
to commence important structures in situations where they are supposed 
to exist. 
It seems not improbable, that the sulphate of lime has been formed 
subsequently to the deposition of the strata of limestone, in which it is 
found, and that it may belong to that class of bodies whose formation 
is continually going on. The decomposition of the sulphuret of iron, 
and the subsequent action of the sulphuric acid thus produced, upon 
limestone, has by some been proposed as the mode in which this is ac- 
complished. But a formidable objection to this view is, that iron pyrites, 
although a very common mineral, is not yet found in sufficient quantity 
to account for the vast results which have been ascribed to it. Thus in 
the western part of New- York, the occurrence of gypsum, the forma- 
tion of vast beds of iron ore, and the production of the immense num- 
ber of sulphur springs which are known to exist there, have all been re- 
ferred to the decomposition of this single mineral. 
If all these phenomena were really due to the decomposition of iron 
pyrites, it would be fair to infer that this substance existed in enormous 
quantities, and that beds of oxide of iron, resulting from this decompo- 
sition should uniformly be found in the immediate vicinity of our plaster 
beds and sulphur springs. But the facts in the cases do not accord with 
the theory. 
