PREFACE. VU 



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 aAvare 

 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 distmction 

 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 1 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 

 giv^en 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 : conflieting views prevailed concerning it ; and it 

 was thought justifiable to make a strenuous and final efibrt for the settlement 

 of the question. 



To show that I have not been indiiferent 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 



