Mankind has been attempting to build low-cost concrete houses for many years. In 1907 Thomas Alva Edison announced a “new method of building dwellings of small cost. ” (1) Edison said: “There is nothing particularly novel about my plan: it amounts to the same thing as making a very complicated casting in iron, except that the medium is not so fluid. Someone was bound to do it, and I thought that I might as well be the man, that’s all. ” (1) Edison’s announcement stirred up quite a controversy. Over the next fourteen years, more systems were proposed for the building of concrete houses. In 1921 H. A. Mount claimed that Simon Lake, of torpedo boat fame, “has found and removed the flaws in Edison’s plan. ’’ (2) He, along with Robert C. Lafferty, a New York architect, developed an elaborate modular system that is very similar in many respects to that presently being used by H. B. Zachry Company of San Antonio, Texas. Lake’s house module was “12 1/2 x 28 feet. ” (2) Zachry’s module varies in length from 28 to 37 feet and is 13 feet wide. Lake’s plan as stated was “. . . instead of building the house on the lot, necessitating a vast amount of labor for putting up and tearing down expensive forms, he will build monolithic concrete units from standardized forms in well-equipped factories, and deliver the finished house, ready for occupancy, to the lot! ” (2) This is exactly what H.B. Zachry Company is proposing and has very nearly succeeded in doing economically.