276 THE FRUIT GROWERS GUIDE. 



In general, air is best admitted by both, as the wind enters by one side, and passes 

 through and out at the other, as shown by the arrows, and sucks out the vitiated atmosphere, 

 without causing a chill by a down draught, such as occurs when one (m) is closed, and 

 the other (1) open, as indicated by the arrows inside the house. The 1 J-inch hot-water 

 pipes keep the roof lights free in severe weather, take off the chill of cold air, and snow 

 cannot lie on the glass. The three-quarters span-rooofed house should face due south. 



3. Span-roofed Vinery. This style is fashionable and generally useful. It affords 

 abundance of light and a large amount of roof space. It is a good form for mid-season 

 and late grapes. The best results are considered to be obtained by placing the ends due 

 north and south, but when convenient we find it better to dispose the house the same 



Fig. 85. SPAN-BOOFED VINEET. (Section through Jl, K\, Ground Plan, Vol. I., page 71.) (Scale : inch=l foot.) 



References : n, ground level ; o, retaining wall ; p, outlet drains ; q, drains lengthwise of borders ; r, rubble 

 drainage ; s, outside borders ; t, inside borders ; u, 4-inch hot- water pipes ; v, rain-water tank ; w, walk ; x, 1^-inch 

 hot- water pipes ; y, side lights ; z, top lights. 



as ground vineries (page 269). Neither position can be had in many places owing to 

 the site sloping to the midday sun, and there is no objection whatever to the ends being 

 east and west, growing the white grapes on the south side, the black on the north, and 

 providing hot- water pipes under the roof, as shown in the illustration at (x). 



When the weather is cold, wet, or severe, the hot- water pipes in the roof prevent 

 the exposed surface cooling rapidly and secure a regular temperature within the span- 

 house ; a little ventilation expels damp, and ice does not form on the inner surface of 

 the glass in severe weather, as occurs when roof heating is not employed, the grapes then 

 being spoiled by the water falling on them as the ice thaws. 



TRAINING. 



The " cut-back " vine (Fig. 78, #, pruned as marked at #, page 261) to two buds 

 produces two shoots ; the weaker is rubbed off ? the other retained. Place a small stake 



