CLIMATE OF NEW -YORK. 207 



ture as it regards composilion, height, slope, etc., all have their 

 influences in a greater or less degree. 



. There are a few other general considerations in regard to cli- 

 mate, which it may be well to state in this place. We notice first, 

 the globular figure of the earth. A body of this form receives the 

 greatest number of rays from the sun on a given space, when they 

 fall vertically upon it. In the second place, the space over which 

 the sun approaches to verticality is increased by the obliquity of 

 the earth's motion in regard to the plane of the equator. By this 

 arrangement the sun apparently travels over a broad zone, equal 

 to 47° in breadth. Then again, the diurnal revolutions of the earth 

 produce the agreeable changes of day and night and an innumera- 

 ble number of other important modifications of temperature. 



It is perhaps impossible to conceive of all the results which 

 must have followed had these several arrangements been different- 

 ly disposed. If, for instance, the axis of the earth had been placed 

 perpendicular to the plane of its orbit ; in this case, the sun would 

 have been always vertical to the same places and those places 

 would have been, as a consequence, burnt, or parched with heat, 

 but in consequence of the obliquity of the axis, the extent of the 

 temperate zones has been produced far towards the poles, and 

 has thereby rendered most of the earth's surface a fit abode for ani 

 mals and plants. 



The atmosphere also, from its great mobility, is an agent for 

 distributing heat ; it not only rises upwards, but is impelled for- 

 wards i moving over the surface of the earth with rapidity in some 

 instances, and at the same time bearing along and distributing the 

 'caloric imparted to it from the earth. 



The temperature too, of the current itself, is modified by the sur- 

 face over which it passes. Traversing a low, sandy plain, it be- 

 icomes hot and dry ; over the sea, damp and chilly ; and over 

 jhigh mountains, cold and pinching. 



Such are some of the causes which operate generally in modify- 

 ing climate. 



Leaving these general views of climate, we pass to the conside- 

 ration of the climate of New-York. In pursuing this subject, it is 

 perhaps unnecessary to say, that it is also modified more or less by 

 ill the circumstances which have been enumerated. But in order 

 hat we may have a full understanding of the climate of the state, 



