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The ceiling of the cellar should be of sheathing paper cov- 

 ered with boards. It must be tight. If there is to be a build- 

 ing over the cellar its floor will make the other side of an air 

 space for protection from cold. If no building is put over 

 the cellar the ceiling timbers should be tightly boarded over 

 on their upper sides. 



The ventilating system used in common storage houses de- 

 pends on the natural law that warm air rises. It consists of 

 a series of cold-air inlets and warm-air outlets. The inlet 

 flues should be placed in position so that they open to the 

 outer air at the ceiling of the cellar and just above the ground 

 level on the banked side of the cellar. Unfortunately there are 

 not available any accurate data as to the relative size of 

 these openings to the size of the cellar. In some localities a 

 ratio of 1 square foot of inlet per 1,000 cubic feet of cellar 

 space has been found satisfactory, while in others it has been 

 necessary to increase this proportion greatly. It is easier to 

 err on the side of too little rather than too much. These 

 openings should be not less than 12 by 24 inches in size, and 

 the flues running from them should extend to within 6 inches 

 of the cellar floor. They should be equipped with tightly 

 fitting shutters and dampers. 



This space between shutter and damper gives the air-space 

 protection needed to keep out frost. These flues must be of 

 tight construction to insure eflacient working. There should 

 be one for each 15 feet of length of wall. This allowance is 

 in accord with the best information available at the present 

 •time. 



Warm-air outlets to furnish the rest of the circulation sys- 

 tem should be placed in the middle of the lengthwise center 

 of the cellar, leading from the ceiling up through the roof. 

 They act in the same way as the chimney of a house, giving 

 a draft that sucks out the warm, foul air. They should be 

 of a size to equal approximately in total the square foot area 

 of the inlet flues, but will need to be only one-half the num- 

 ber. They should be equipped with tightly fitting shutters at 

 the ceiling and dampers above. 



In constructing a storage cellar it is advisable to build a 

 packing room as an adjunct to the plant. This may well be 



