Issue 1

Dovetail corrugated steel sheeting consists of flat steel sheets, crimped into the form of dovetails, and is usually crimped in three depths, viz., No. I of 3/4in. The maximum size of sheets is 3ft. 9ins. wide, that is, in the direction of the corrugations, and 5ft. 6ins. in length, or across the corrugations. The sheets vary in gauge from 20 to 28. It is only section No. 1 (3/4in. in ,depth) that can be crimped to 20 gauge. M. Noel Ridley

The concrete ship has arrived and has undoubtedly come to stay in spite of all the cheap witticisms and gloomy prognostications. Every new idea is greeted in the same manner-railways, steamships, motor cars, the use of electric power, have been in turn greeted with a chorus of condemnation; to be unaccustomed is in fact to be criminal. J. S. E. De Vesian

The subject of this paper is well worthy of the closest attention by all, and the Concrete Institute is to be congratulated upon having decided to place before its members some aspects which may appeal to them in connection with their work, as well as a wider view of the whole matter as it may affect the industrial world in this country in the future. Edward Willis

GENTLEMEN.,-I have to thank you for electing me as your president, an honour which I highly appreciate. Glancing at the last Annual Report, I think you will agree, that it is satisfactory to find in these difficult times, that the membership is 981, as against 978 last year; if we can hold our own to the end of the war, I feel certain that we shall get a large increase in the membership when the demobilisation of the troops takes place. H. D. Searles-Wood

"Tell me not in mournful numbers, Houses are not what they seem, For the walls that look so solid, Once were poured from cans like cream." The conservative instinct in some of us tends to strengthen our prejudices. And a fondness for hand work and the qualities of familiar building materials make one shy of the mystical concoctions that are more or less mingled with brains. Concrete seems one such that depends on conscience. The man that mixes the material must exercise his conscience, and who can measure the amount or tell its value? A brick seems more frankly to proclaim its qualities, and as with stone and timber, we know from past experience all that it can do for us. But concrete is an unknown quantity to many of us, except perhaps when used in its simplest form, as for foundations. Another element of my prejudice is due to the recollection that greed is gratified by the use of concrete construction. That is to say, the shopkeeper who is out to make money wants to seize every inch of space. He thinks the display of his wares is better for him the more vast it is. Beauty has no charm for him and quantity is of more value than quality. The shopkeeper little realises how the mind and memory are debauched by vast crowds of articles jostling each other for attention. When a myriad of objects all shout at once, "look at me!" we can carry away no! lasting memory of anything but chaos. Concrete construction has helped in this direction. Meanness and greed I say are its parents. What can be expected from such an ancestry? C. F. A. Voysey

The design of Steel Structures is a task very often undertaken without a reasonably sufficient knowledge of the principles involved. A widespread distribution of pocket books containing data and tables, provided primarily as time-savers, has enabled the recipients to utilise a limited knowledge of the theory of structures without, unfortunately, exercising a rational limit to its application; and whilst there is in existence authoritative control over misdirected effort where such endangers haman life, there is no such control-except in competitive designing-over the waste material and effort expended in the manufacture of structures the design of which is inefficient. Hence it is very advisable that purchasers should take every precaution to secure expert service to meet their needs, and to remember that what at first sight appcars to be cheap may ultimately prove costly. Albert S. Spencer

The essential constituents of concrete are the aggregate, or lumps of broken materials, and the matrix, or binding substance, which is usually cement or lime. Frequenty sand is also added to the mixture, or a fine-grained concrete may be made from sand and cement alone. The American connotation of the term "aggregate" includes sand. P. G. H. Boswell