THE CONCRETE AGE

Evening Star, Issue 19666, 20 September 1927, Page 2

THE CONCRETE AGE

£By Chalmeks W. Thomson.] It is said that, even as we already refer to the past 100 years as the “ Iron Age,” so historians will refer to the twentieth century as tho “ Concrete Age.” In tho first third of the past century marked development occurred not only in the production and universal application of iron, but in the cheapening of it, so that it came within the reach of all, and in tho commercial methods of combining it with predetermined amounts of carbon, depending on whether it was needed soft, or tempered for edge tools, or in pig for casting into moulds. Similarly in this century, and plain for all to see, there has been a remarkable development in the universality of application of cement, in the cheapening of cement products, and even, as with iron, in tho practical combination of it, not alone with sand or stone into concrete, but with other minerals fox- the manufacture of goods which seem certain to at least largely displace iron in many spheres. It is known to most that one firm in Dunedin manufactures many huge concrete pipes, compacting them by centrifugal force in a few minutes, although th'/ may weigh a ton. Not many years ago such pipes were laboriously built up by hand, and were neither as good nor as cheap as those produced to-day. By centrifugal force fiat paving slabs are similarly produced in other lands infinitely better, cheaper, and quicker than by the more primitive methods, which, however, pertain still in New Zealand

Another Dunedin firm not only produces well-known lines in concrete (sand and cement), but lays roots with corrugated sheets similar in appearance to iron, but made from cement and asbestos. This combination gives strength with longevity. The cement hardens with age, and the asbestos, being fibrous, supplies tensile strength, which in cement is low. Asbestos is an indestructible mineral silicate, which is also well known for its non-conduc-tivo properties. The result of this combination is therefore a material which without maintenance is permanent, non-conductive (and therefore free of frost-drip), and the equal of galvanised iron in appearance, which unfortunately is no great claim to make.

The same firm also combines cement with pumice for fuel boiler casings, and cement with marble for many artistic purposes. In the former case pumice, being one of the best-known non-con-ductors. and being unchanged by the heat of fire, when bound with cement makes an idea! insulation, keeping the washhouse cool by retaining all the beat of the fire around the copper. This pumice and cement combination has already to a great extent right through Now Zealand displaced iron and brick boiler casings. The marble and cement combination lias the virtue of novelty in this part of the world, although for long well and favorably known elsewhere, but beyond the reach of any except the rich or the architects of great public buildings in tho older lands. .Marble and iimo combinations were used 200 years ago, and can be seen to-day in tho flooring of such ancient cities as Pompeii and Herculaneum, in Italy. By modern methods terrazzo, as the Italians have taught us to call it, is brought within the reach of all, not only for the flooring of halls and porches, but for such everyday things as sink tops, baking and other slabs, and for doorsteps, in which field it is certain to oust the familiar and workproducing brass step. It is a revelation to those who look on concrete and cement combination as rough and cold. Glassy smooth and scintillating, it has all the polisli of finest -marble at half its price, and in an infinite range of colors and effects.

Ours is,indeed the concrete age. Let ns -watch' its growth and grasp the opportunities which the ago places to our hands. So shall it the quicker cater to man’s growing needs, and those of ns with vision shall not miss that tide in the affairs of man, which, taken at the flood, leads on to fortune.