202 AMEBICAIT POMOLOGY. 



consequence of this condition of the atmosphere, which 

 depends upon the large amount of caloric that is present 

 in the latent fonn, in the vapor, and which becomes sensi- 

 ble heat as fast as the moisture is condensed ; as well as 

 by the sensible caloric, the absolute warmth of the water, 

 affecting the temperature of the atmosphere. 



We thus see that very opposite situations, in regard to 

 "mere elevation, may both be recommended for orchards ; 

 but the latter are the exceptions rather than the rule, for 

 we can not always count upon the saving influence of a 

 fog, nor are the modifying effects of a moderate sheet of 

 water always to be depended upon at the time when most 

 needed. Still, we may find a few favored spots, where an 

 insular position, in a lacustrine situation, receives a double 

 influence — acting at both ejctremitios of the season of 

 vegetation, in quite an opposite way, but in both acting 

 favorably. In such places we shall discover that the spring 

 opens late, being retarded by the cold atmosphere flowing 

 over the chilled waters, that may be even icy, when inland 

 places in the same latitude are-rejoicing in a mild and ge- 

 nial temperature, tempting the expansion of the flower- 

 buds. Vegetation on an island thus situated is retarded 

 imtil all danger of frost has passed, and the air has re- 

 ceived the full benefit of warmth from the water. 

 Then, again, in the autumn, when we are in danger from 

 the access of an early frost, such as sometimes, north of 

 latitude forty degrees, destroys the whole crop of com, 

 almost universally, over hundreds of mUes, these favored 

 spots have really a warmer atmosphere, from the influence 

 of a great extent of water, that has enjoyed a summer's 

 sunshine, and which warms the air by giving off its heat 



