64 ON THE CONSTRUCTION OF WALLS. 



degree of warmth ft*>m the reflection of the ground. 

 Hence, grapes growing within two or three feet of the 

 bottom of a wall facing the south, will, in general, 

 ripen from ten days to a fortnight earlier than those 

 growing on the upper part of it. There is a disadvan- 

 tage, however, in training grapes near the ground, as it 

 respects their remaining on the vine after being ripe. 

 If grapes can be kept perfectly dry, they will hang on 

 the vine, and improve in flavour, for a long time after 

 they are ripe ; but if dampness or moisture of any de- 

 scription reach them, the consequences are quickly 

 seen in the decay of the berries. After the middle of 

 October, therefore, it will be found a difficult matter to 

 preserve grapes that hang within two feet of the ground, 

 on account of the damp exhalations that continually 

 arise from the soil at that period of the year. 



If walls be built for the express purpose of producing 

 grapes, the most judicious expenditure of the materials 

 will be in the erection of several low walls, not more 

 than six feet high, in preference to a small number of 

 very high walls. For the purposes of pruning and 

 training, and the general management of the vines, 

 walls of this height are far more convenient than those 

 of a greater height ; and if built to run directly north 

 and south, the entire surface of both sides of each wall 

 will be available for the training of the vines; and as 

 snch walls need not be built at a great distance apart, 

 an astonishing quantity of grapes may be thus annually 

 grown on a small extent of ground, by the erection of 

 a few walls of this description, built parallel to, and not 

 far distant from each other. 



The best materials for the construction of vine walls 

 are, without doubt, bricks, as they present a more 

 even surface than can be obtained from walls built of 

 any other description of materials ; and evenness of 

 surface is a quantity that cannot be dispensed with. 



