26o Vineyard Culture, 



so the higher shoots on a grape-vine may escape when the 

 lower ones will have suffered. The moisture of the air has 

 nothing to do with the cooling and freezing ; indeed, theoret- 

 ically, quite the contrary. The least motion iji the air will 

 prevent the occurrence of a frost, because, so soon as a layer 

 of air, in contact with the radiating surface, is cooled, by giv- 

 ing up its heat to that chilled surface, it is borne away by the 

 breeze, and mingled with the great mass of warmer air above 

 it, and its place is occupied with a fresh supply of the warmer 

 fluid. Every one knows the difference in the result of a still 

 and windy night, even when the sky is perfectly clear, and 

 the radiation is going on equally in both cases. 



These views are confirmed by the venerable editor of the 

 Western Ruralist, Lawrence Young, of Louisville, Kentucky, 

 who has long been a successful fruit-grower, and a close ob- 

 server of the influence of meteorological changes upon our 

 crops, and of the mode in which they affect them. 



In an article in the April number of that paper, when dis- 

 cussing the injury to the peach crop of the past winter, he 

 says: 



" The intense cold of our climate comes upon us in one of 

 two ways, either by radiation, on still nights, or is brought 

 to us in winds charged with the frigid temperature of the 

 Rocky Mountains, generally moving in the wake of some rain 

 cloud, and with the velocity of a gale, measuring sixty to 

 ninety miles per hour. In the latter case, the driving force is 

 so much greater than the power of gravity, that in passing 

 over obstructions, such as hills, or dense forests, there is a 

 volume of atmosphere on the lee side of such obstructions, 

 below the cold wind, and undisturbed by it; just as is often 

 seen in a hurricane crossing a valley, the trees will be thrown 

 right and left to the edge of the first hill, and the work of 

 destruction will be renewed as soon as the hurricane crosses 

 the valley, and reaches the opposite hill, but not a tree will 



