CONSTRUCTION OF VINERY. II 



inch all round the pipe inside the sheath. This cavity 

 is fed with fresh air from the exterior of the house 

 by a pipe 5 inches in diameter, which springs from 



FIG. 5. 



HOT-AIE VENTILATOR. 



the lower surface of the sheath, and passes through 

 the front wall of the house to the external air. There 

 is a valve in this feed-pipe to modify the supply of 

 fresh air at pleasure. In the upper surface of the sheath 

 is a double row of small holes, so that the moment the 

 cold air comes into the hot chamber round the pipe, 

 and gets hot, expanded, and lighter, it makes its exit 

 through these holes into the general atmosphere of the 

 house. In our early vineries last winter (1861-62), the 

 valves were kept open constantly, both night and day, 

 with great advantage to both fruit and foliage. 



CONSTRUCTION OF VINERY. 



As a rule, whether for early or late forcing, I prefer 

 a good-sized house say, height of back wall, 15 feet; 

 width of house, 15 feet; height of front sashes, 2 feet; 

 length, 40 feet. A house of these dimensions has a 

 good length of rafter, which enables the vines to carry 



