This is a utilitarian age. People desire houses to live in--not to look at, although every one will readily agree that a certain regard must be paid to external æsthetic considerations. The average house-owner troubles his head very little over the outside appearance of his domicile or the materials of which it is built, so long as the interior offers him all he desires in regard to comfort and health. Too long have we clung tenaciously to specific theories which are no more adapted to this age than is the slave-oared galley to mercantile traffic. They are destructive rather than constructive. For a time such clock-arresting dogma and precepts hold sway, but sooner or later the pendulum of progress gives such a vicious kick as to break down the whole of the obstructions disputing advance, to assume rhythmic running in a new channel to the advantage of one and all. Science has the solution to the housing problem ready for immediate application, but she must be allowed to pursue her progressive way untrammelled. From what one might be able to assume, brick and stone represent the only building materials at our command. But are they? In other fields, where restraining forces are not allowed to secure the upper hand, huge forward strides are being made and with a material we, as a supposed commercial nation, have scarcely noticed. I refer to concrete. We have only to turn to the engineering world to see what has been achieved with this material in the construction of bridges, tunnels, piers, harbours, breakwaters, warehouses, lighthouses, and even ships. If we turn to the United States and Germany we are able to see how we have lagged. In both those countries enormous strides have been made and incidentally, in the prosecution of this task, other magnificent conquests in the world of science and of the industrial employment of waste are recorded. To-day the manufacture of cement constitutes one of the twelve most important industries in the United States, and the greater part of this material is made from what a few years ago was accepted as sheer waste--residue from the iron-works which, having no further ostensible use, was dumped in huge piles to the disfigurement of the landscape. To-day this waste is being turned into building material, having usurped the product originally selected for this duty.