PREFACE. 
vii 
more than a few of the most important places in the State, for the purpose 
of collecting the necessary specimens of soil; and those who are practically 
acquainted with the processes of analytical chemistry, and who are aware 
of the great care requisite to secure reliable results, will not be surprised that 
many of the inquiries are but partially completed. 
It will be seen that I have laid some stress upon the division of the State 
into maize (or indian corn) and wheat-growing districts. The distinction 
may be one of little importance, and some may regard it as useless; still I 
believe that the actual constitution of the soils, and of the rocks from which 
they are derived, will bear me out in the distinction itself. 
The origin of the phosphates has been with me an object of considerable 
research, in which I trust I have obtained some satisfactory and useful 
results. I believe this is the first attempt, made in this country, to determine 
the rocks which contain phosphates, and distinguish them from those that 
do not. I consider the inquiry an interesting one, which ought to be further 
prosecuted. 
It may appear to some that I have devoted too much time and space to 
the consideration of the Taconic system. It must be remembered, however, 
that in giving an epitome of the New-York rocks, it was necessary that the 
rocks of this system should be noticed also; and inasmuch as the question 
respecting their age was one which had occupied our most distinguished 
geologists, and was in itself highly interesting in many points of view, I 
deemed it proper, considering the impulse which the State of New-York has 
given to geological inquiry, to press the matter to a conclusion, by settling 
definitely the era of the rocks of this system. The system belongs pre¬ 
eminently to New-York : conflicting views prevailed concerning it; and it 
was thought justifiable to make a strenuous and final effort for the settlement 
of the question. 
To show that I have not been indifferent to the utility of my labors, I 
may state that I so divided my time as to secure the greatest economy. The 
summer, being the only season when outdoor observations can be made, has 
been spent mostly in the field, and the winter in the laboratory. In the 
field, I have been assisted by my son, a part of his expenses being defrayed 
by myself. In the laboratory, Mr. Salisbury, and L. Chandler Ball, Esq., 
were occupied steadily and unremittingly for three hundred days, without 
B 
