By Mr. George Siiiells. 



527 



stronger fires than we now use were required in August and Sep- 

 tember, to ripen the fruit and wood. 



I calculate the expense of heating the wall for a season will not 

 exceed 30*. upon an average of seasons.* Our vines upon the wall 

 are never attacked by the Red Spider or any other insect ; the 

 foliage is large and healthy, although we do not apply the engine 

 above three or four times during the season. 



Black Hamburgh Grapes begin to colour about the 6th or 10th 

 of August, and some are ripe in the latter end of September, or 

 much earlier in fine seasons, if required. In the beginning or 

 middle of November what remains of the crop is cut, and preserved 

 in a dry airy room ; the fire is then discontinued (for we keep a 

 little fire heat until the crop is off), and in a week or two after- 

 wards in mild weather we prune the vines. 



The wall is twenty-one inches thick and covered with a saddle- 

 backed coping which projects four inches on each side, and has a 

 small groove under the edge to intercept the water which flows 

 down the slope of the coping. It is about fifteen feet high, and 

 the length, which is occupied with vines and wrought by one fire, is 

 about thirty-six feet. 



A rough sketch of our mode of training accompanies this notice. 



* The usual price of coals at Glasgow is from 8*. to 10s. per ton. according to 

 the quality and season of the year. We use dross for our forcing houses and flued 

 walls, the usual price of which in Glasgow is ahout 3s. 6d. per ton, or delivered 

 here 5s. per ton. Some of it is pretty round and for steady fires we prefer it to 

 large coals. 



