Show some substitute for raw L fear expressed for raw lumber wm will have to be found if we are to continua lumber supply nc the present rate of building 1 g u construction it is not by H A jeffries builder chicago a r 11 1 3 imagination that our raw m uLi iL lumber supply is rapidly becoming exhausted but an actual problem conceded by all who have to leal with it the forests of pennsylvania are practically gone and those 1 if I the middle north are rapidly disappearing the yellow pine of the south and adi the fir trees frees of the northwest must now supply not only 1 the it 6 lemand iemand of their own sections but those of other sections where the trees save alave ilave disappeared re enforced concrete is the best substitute that has yet been found this was discovered in the early sixties by a french gardener monier by name who found himself in difficulties because of a lack of tubes for his plants he contrived a temporary tube made of wire mesh plastered with mortar and this proved so good a substitute that he made all of his tubes in that manner concrete is composed of broken materials of various kinds and sizes known as the aggregate which is thoroughly mixed with concrete when subjected to tension stress this material is very weak and to overcome this defect rods of iron or steel are placed in the concrete and the material is then known as re enforced concrete it was first introduced in building construction with the idea of making fireproof buildings and in this was successful but lumber was still required and until some form af f construction that will eliminate entirely the use of lumber in the building of houses is discovered we shall always be confronted with the problem f a lumber famine |