CLIMATE OF NEW-YORK. 209 



been cut off by frost in August, at the base of the highest of the 

 Adirondacks. 



East of the Hudson there is another belt of high land, ranging 

 nearly north and south, which is laid out in narrow ridges, which 

 geologically consist of slate and limestone. These are prolonged 

 into Canada, They probably present a medium height of ] ,000 to 

 1,200 feet, but rising occasionally to 3,500 feet. The vegetation 

 npon the top of these ridges, when they rise above 1,000 ft., shows 

 merely the effects of the northwest wind, in the diminished height 

 of the trees and their more shrubby growth; but they produce no 

 where an Alpine vegetation. South of the Mohawk valley a hilly 

 country prevails in all that region which is commonly called the 

 Heldcrberg. South of this hilly range^ and west of the Hudson, 

 the Catskiils form another important mountain chain, though less ele- 

 vated by 1,800 feet than the Adirondacks. As a whole, then, New- 

 York presents a surface greatly diversified — in some portions rising 

 into very respectable mountains, in others it is depressed and tra- 

 versed by long parallel valleys j only a small portion of the sur- 

 face is of that character which can be denominated level. 



With these remarks, we proceed to speak of the temperature of 

 New-York, and in this connection it is proper to remark that the 



suits which are given in the following pages were obtained prin- 

 ■ipally from the Regents' Reports, and from a paper prepared by 

 Mr. James H. Coffin for the agricultural survey of the state, now 

 in progress. These reports are made up from the returns of fifty- 

 eight different localities, at which meteorological observations have 

 been kept. These localities are scattered over a great variety of 

 surface, and hence they indicate pretty fairly the climate of the 

 state, or rather the meteorology of the state. The mean tempera- 

 ture of the fifty-eight places at w^hich observations have been made 

 for seventeen years, is forty-six degrees forty-nine minutes, but, as 

 already remarked, the relative temperature of different sections of the 

 state, while it depends chiefly on latitude and elevation, is modified 

 by the circumstances already stated. 



From numerous observations made within the limits of the state, 

 It is very satisfactorily determined that the rate of decrease in tem- 

 perature amounts to 1° for 350 feet of elevation ; from some ob- 

 servations the rate is greater, and in some less ; but as this is near 



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