206 THE FRUIT GROWER'S GUIDE. 



with metal slides affixed for closing or opening. The ventilator should have a wood 

 cover which, by mechanical contrivance, can be raised or lowered from the interior, 

 and the lower part of the casing must have a wood shutter, closed or opened with a 

 line and pulley. With a 2-inch iron pipe inserted at each corner of the building 

 and midway of each side through the outside wall just above the damp-course, opening 

 into the air cavity, each pipe having a screw valve outside, the air cavity can be 

 ventilated by raising the roof ventilator and pushing the slides off the openings in 

 the ventilating case, regulating the current by the valves. To ventilate the room 

 simultaneously by the air cavity, lower the inside shutter, and the air, entering by 

 the 2 -inch pipes at the bottom of the cavity, passing up the wall and ceiling space, 

 rushes out by the holes in the sides of the ventilating case, and out by the rool 

 opening, sucking out the vitiated atmosphere of the fruit room without disturbing 

 it perceptibly. When it is desired to keep the air in the air cavity still, the slides 

 are kept over the holes. The ventilator then acts separately, damp being expelled 

 by a circulation of air induced by opening the windows, or a gentle warmth in the 

 heating apparatus. 



If the building must be a lean-to against an existing north wall, as commonly 

 occurs, there being a vinery or peach-house on the south side, the existing wall must 

 be isolated from the intended fruit room, for, though 18 inches or more thick, it is 

 in contact with wet soil at its foot, damp striking up a yard or more, and the upper 

 part is warm, if not damp, and therefore prejudicial. A 9-inch wall built in cement, 

 with proper foundation and damp course at the ground level, 4J inches off the 

 existing wall, fixing ventilating pipes at each end of the cavity near the bottom, 

 with corresponding openings at the top immediately under the wall coping, completely 

 protects the room from damp and heat. The openings in the air cavity should not 

 be closed, but the cavity in the wall at the other side of the room, and at the 

 ends, must be ventilated independently of the back wall area. A 2-inch pipe, with 

 valve, introduced through the outside wall into the air cavity at the upper angle 

 of each end next the back wall, will insure a thorough draught, if corresponding pipes 

 are fixed at the lower part, as already described. To ventilate the fruit room a casing, 

 18 inches long and 9 inches wide in the clear, fixed in the 9 -inch wall at every 9 feet, 

 just below the under ceiling, and closed on the inside by a flap door regulated by a 

 cord and pulley, meets every requirement, but the opening must be continued in the 

 wall., and communicate with the external air above the roof immediately under the 



