48 OPEN AIR GKAPE CULTURE. 



the best direction for the trellises on which the vines 

 are trained. We have often seen a north and south 

 direction advised under the idea that the vines thus 

 receive the sun's rays for a longer time. But the 

 evils attached to this plan are great and insurmount- 

 able. In the first place, the vines receive the full 

 force of the early morning sun which, striking the 

 young leaves while still cold, and it may be partially 

 frozen, is productive of the most injurious effects. 

 Then as the day progresses toward noon, the vines 

 are so shaded as not to receive the amount of heat, 

 which they would gladly enjoy at that time, while 

 toward evening again their excitability is greatly 

 increased and is kept up until the last moment, instead 

 of the exciting influence being quietly withdrawn as 

 it ought to be. 



But if we give our trellis a direction from east to 

 west, instead of from north to south, the vines will 

 expose but a small surface to the first rays of the sun 

 which will thus warm them gradually, until it attains 

 its meridian splendor, when it will exert its full power 

 and then gradually decline until evening, when 

 everything will gradually cool down. Sudden 

 changes are thus avoided, and the full power of the 

 sun is secured in the ripening of the grapes. 



Intimately connected with the foregoing subjects, 

 are the laws which regulate the influence of tempe 



