Page:Popular Science Monthly Volume 90.djvu/695

 Popular Science Monthly

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��A Hollow Tile Building Block Which Is Waterproof

IF we take the word of the hollow tile enthusiasts, brick houses are disease breeders, since brick does not keep out moisture or the cold and does not retain heat. Another argument against its use is that it permits water to go through to the inner surface of the wall, making it necessary to use laths or other means to separate it from the plaster. Laths are not used with hollow tile.

The widespread popularity of the hollow-tile building block in prefer- ence to brick in the construction of our modern buildings is said to augur well for its exclusive use in the future. Of course, there are many different kinds of building blocks of the hollow tile type, all claiming to be waterproof and weather resisting. The one illustrated is the invention of Halver R. Straight, of Adel, Iowa. Between a layer of cement or mortar and each rib there is a dead-air space which prevents the flow of water or the transmission of moisture.

The inventor claims that if water enters the vertical mor- tar joints be- tween his tiles it will not flow toward the inner surfaces of the wall, but will be conducted back to the outer sur- face. Each tile contains two re- cesses for cement or mortar, a rib, a groove, and a top and bottom surface which in- cline downward from the groove. The rib of one tile fits into the groove of another, so that the blocks can be alined with exact- ness. Fuithermore, the tile does not need to be hammered or pounded upon to force it down in its proper position.

���The kerosene oven, from the nearbv tank.

��A copper tube brings the oil A hand pump suppHes pressure

��Army Cooks Prefer Kerosene Wood for Fuel

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���Above: A house built of hollow tile. Below: A type of hollow tile through which moisture cannot enter

��SLOPING Tl

��GROOVED INNER FACE OF WALL RECEIVE PLA5TtB

��MORTAR

���CtNTERIi:0 RIB

��ARMY camps along the Mexican border ^ are experimenting with kerosene as a fuel substitute for wood in the field bakery ovens. In localities where wood is scarce, oil is much cheaper and more reliable than wood, and there is no danger from sparks. A simple burner is used. It consists of a piece of pipe extending the length of the

fire box and con- taining a num- ber of holes through which the oil is forced under pressure. A flexible copper tube brings the oil to the burner from a nearby supply tank hold- ing about fifteen gallons. Pressure is applied to the oil by means of a hand pump, the amount being deter- mined by a gage.

By burning oil an oven may be brought to a baking tem- perature in less time than when wood is used. The baking can be started at any time on short notice and the bakersdo not have to contend with wet or green wood.

��GROOVE FOR ACCURATE NEMENT

��MORTAR GROOVE

��MINIMUM MORTAR JOINT ON OUTER FACE OF WALL

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