136 CULTURE OF THE GRAPE. 



the branches ; " but we must bear in mind that currents 

 of cold air are almost entirely in a horizontal direction. 

 Of course, then, the perpendicular trellis will receive the 

 full force of the wind, like a spread sail ; while the hori- 

 zontal cuts the wind like a knife, presenting far less sur- 

 face for resistance than any other form. In this consists 

 a very decided advantage for the horizontal plane ; but it 

 is true that the wind will strike the outer foliage with full 

 force as it passes over the trellis. This same foliage is 

 again exposed alternately to the fierce heat of a direct 

 sun, and the cold air and heavy dews of night. Such 

 fluctuations are not favorable. It is noticeable that the 

 outer and more exposed foliage of the grape is, in gen- 

 eral, most liable to mildew. Whether this fact, as applied 

 to the horizontal trellis, will prove a serious objection, 

 can only bo determined by actual trial. While horizontal 

 training of fruit-trees has been suggested, and a partial 

 and modified form is almost universally adopted for the 

 grape under glass, yet as a complete system, and for 

 open culture, I am not aware that the form given above 

 has ever been tried ; but I think it is so plainly suggest- 

 ed by the natural habit of vegetation, and that it secures 

 so many theoretical and practical advantages, that it is 

 worthy of the most careful trial. If the vines can be 



