THE DAWNING AGE OF CEMENT Concrete has come to be a dominating factor in the building world. Its invasion of the mod ern structural field, and triumphal progress therein, have already wrought a revolution; and its present widespread and rapidly increasing application to construction work of all kinds is the marvel even of this age of wonderful en gineering achievement.
When, not many years ago, the steel-frame structure supplanted the historic masonry and timber, it worked a far-reaching transformation in building methods and materials, which was soon reflected in the external appearance as well as internal arrangement and details of new structures of almost every class. The sky-lines of cities and towns assumed new forms; and especially in the larger industrial centers, the very face of things was changed.
With the advent of a true Portland cement concrete—the handmaid of steel—still another and greater era of structural and industrial evo lution was ushered in. Nothing in all the won derful annals of American industrial develop ment has ever equaled the expansion that has characterized the Portland cement industry during the period since the year 1898. There are in fact many who, in view of the marvelous growth of cement manufacturing in America during these opening years of the twentieth century, and the wonderful versatility of this new structural agent, as shown by innumerable examples of its application to all kinds and grades of construction, are already proclaiming that the Age of Cement is upon us. Just as in the manufacturing world the successive eras of power development can be traced through the stages of human labor, water power, and steam power, to the present dawning age of electrical power, so, in the building world—we are told— the claims of wood and stone and brick and tile and iron and steel have now to adjust them selves to the urgent demands for recognition of concrete as a structural factor which is not only capable of supplementing them to advantage, but in many respects far surpasses them all.
In any country subject to rigorous climatic conditions such as prevail in North America, with its excessive changes of temperature and humidity, no natural building material exposed to the elements will withstand the ravages of time. Wood, being organic, is peculiarly re sponsive to the disintegrating activity of nat ural agencies, and, unless carefully protected from exposure thereto, is very rapid in its de composition. Under the atmospheric influences ,of this climate, all grades of sandstone will in time crumble back to mother earth; marble is still less enduring; and even the so-called "ever lasting" granite is similarly limited in its life. Steel is subject to oxidation or rust from the combined action of carbon dioxide and water or the direct action of atmospheric oxygen, and to still more rapid chemical corrosion from the action of sulphurous and other noxious acid gases and liquids; and it must therefore be given the closest attention in the application of pro tective paints or other coverings to insure any degree of permanence.
Among building materials, concrete stands out alone as the one which can truly be called "permanent," and which has at the same time the quality of progressive and accumulative strength. It is this characteristic of accumu lative strength—a strength increasing with the lapse of time—which more than anything else gives concrete its advantage over other mate rials in engineering and building construction. Under conditions of exposure that in the case of other building materials would accelerate the natural tendencies to decay and final collapse, concrete displays higher and higher powers of resistance, the action of the elements only add ing hardness and strength as time goes on.
In addition, however, to the marvelous dur ability of concrete under trying conditions— which is, perhaps, its most striking i'eature no other material now used in construction can be said to meet so successfully the combined requirements of versatility in useful application, adaptability to varying structural conditions and combinations, simplicity combined with dignity and stability of appearance, harmonious adjustment to varying environment, cleanliness and hygienic value, and—last, but not least— economy of cost.
No progressive architect, engineer, con tractor, or builder can in these days ignore the claims of concrete as a factor of supreme im portance to be reckoned with in the general field of construction. In spite of early unfortunate experiences with natural cement, and more re cent instances of actual failure—which have been traceable in every case to ignorance or criminal carelessness—concrete has irresistibly forged its way to general acceptance; has tri umphantly risen above prejudice and doubt; and, by its own intrinsic merits, has finally won for itself an assured place as an instrumentality of twentieth century progress whose possibili ties when realized may dwarf the dreams of the wildest imagination. Stronger and more dur able than any natural stone, unaffected by fire or moisture, capable of adaptation to any posi tion or condition, workable by unskilled labor, lending itself easily to any form of ornamenta tion, vermin-proof, cleanly, and comparatively inexpensive, it ranks among the foremost of the valuable gifts to mankind from the treasure house of modern scientific and technical re search.
A widespread popular knowledge of the na ture and possibilities of concrete, the principles of its composition, and the rules of its intelligent use, will react beneficially in a thousand ways upon the life of the community. It will immeas urably increase the facilities of industry and commerce; it will minister to social conveniences and the education of public and private taste; it will make better homes, better municipalities, and a more progressive citizenship. That such knowledge is absolutely indispensable for the efficient working equipment of the modern builder goes without saying.