Page:Popular Science Monthly Volume 91.djvu/797

 Popular Science Monthly

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��ground may be constructed entirely of blocks of sod 2 ft. or more in thickness. One of the most unusual storage houses seen in the course of these studies was built entirely above the ground with the side and end walls constructed of bales of alfalfa hay.

In the more expensive and substantial structures the side and end walls are built of concrete. The roof of the dugout, or cellar storage house, in the region under discussion is generally of unsawed lumber. Usually the rafters are cut from small trees. The whole roof may be covered with poles and these poles covered with straw and soil, or the rafters may be covered with heavy woven-wire fence netting and then with straw and soil.

In sections where rainfall is sufficiently heavy to render a straw or pole-covered roof undesirable, the potato storage cellar is constructed with a water-tight roof. Generally, the roof is covered with rough lumber and shingled. Occasionally a cellar is sheathed with matched lumber on the inside. This treatment provides a fairly well insulated roof, which requires but little further protection except in pro- tracted spells of cold weather, when a layer of straw or strawy manure is ad- visable.

The water-tight roof type of the western potato cellar is admirably adapted to stor- age in the northwestern and middle- western United States wherever good drainage can be secured. Furthermore

��Ventilator. Straw Earth'

���Cross-section of a potato pit with layers of straw and earth and a perforated ventilator

it is one of the most economical types of natural storage.

A ventilator should be so constructed that the opening at the top is protected by a cap, which may be rigid or hinged. It should extend through the roof and into the cellar far enough to permit a swivel damper to be inserted and operated by a

��spring or lever, or else a slide damper which can be opened and closed at will. The ventilator should be of sufficient size to admit a reasonable volume of cool air and facilitate the egress of warm air.

While the total exclusion of light is an

���An insulated frame potato storage house used for storing the second crop of potatoes

essential feature of the construction of a good potato storage house, it is necessary to have some light where workmen are engaged in sorting and preparing stock for the market or for seed purposes during the winter. Usually no provision is made for lighting the storage house by natural light except that which may filter through the ventilator shafts when lifting the ventilator caps, or which may be obtained by opening the doors. This method of admitting light can be employed in winter only during mild weather. Light is ad- mitted in some storage houses by inserting a movable window glass or hinged window in the ventilator shaft. Such an arrange- ment permits the removing of the ventilator cap in severe weather without endangering the stored potatoes by lowering the tem- perature below the safety point. But this does not provide a wholly satisfactory light- ing system, and reliance must still be placed in a lantern or lamp.

��A Paste Lubricant for Starting Screws and Nails

BEESWAX and tallow melted together and put into a box or mold make a very good lubricant for starting nails and screws. Owing to the nature of the materials, this paste also prevents rust. — James M. Kane.

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