Until very recently the only quality of steel which could be used economically for structures of moderate size was the standard 28/33 tons per sq. in. mild steel. Special high tensile steels have hitherto been so expensive that they were useful only for those structures in which the saving in dead weight was of paramount importance. In the United States of America nickel steel and silicon steels have been extensively used for long span-bridges, but so far as the author is aware they have not been used for smaller structures in which there is no special incentive for the designer to reduce the dead load. Gilbert Roberts
THE most readily understood method of dealing with eccentric load (or, which is much the same thing, with bending moment) is that of the Equivalent Axial Load. By this method one takes the total actual load on the column and adds to it an amount to correspond with the bending moment. The sum is called the “total equivalent axial load,” and the column is designed upon it, without further reference to the bending moment. A.B. Dailey
SIR,- Mr. Faber raises a question which requires ventilation and, even more than that, action. The trend to-day is for the architect to become the employer of engineers, with the result that the latter are inclined to suffer. Each of them, whether engineer or architect, follows a profession which requires no adulation on my part, but why should either profession become the servant of the other? Rather, they should work together in harmony. I heartily agree with all that Dr. Faber says in his article.
The CHAIRMAN (Mr. Ewart S . Andrews, BSc., M.Inst.C.E., Vice-president) proposed a very hearty vote of thanks to Mr. Roberts for the excellent material he had provided for study, and for the excellent manner in which he had described the properties of the high tensile steel dealt with.
The CHAIRMAN (Mr. Ewart Andrews) said that he was sure all those present had enjoyed the paper, and, when they had studied it sufficiently well to understand it, they would realise that Mr. Leys had spent a great deal of time and thought in tackling this paper on the very difficult subject that the Americans, he thought, called "soil mechanics.” Mr. Leys had said in connection with one of the diagrams, that Rankine had assumed that a certain line was a straight line. The fact was that he had assumed it was a straight line because that made if easy for him to get his formula! That, indeed, was the reason for all these mathematical assumptions. If one did not make some assumption which enabled a certain simple result to be reached, then, of course, one could not get anywhere.