Popular Science Monthly 



679 



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 



to 



Above: A house built of hollow tile. Below: A type 

 of hollow tile through which moisture cannot enter 



SLOPING Tl 



GROOVED INNER 

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 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 



