Presidential Address

1. Having had occasion during recent years to devote considerable time to structural testing work, the writer has natarally taken some interest in the history of the subject and has prepared the following notes in the hope that they may be of interest to structural engineers generally. As a result, also, perhaps those more expert in this field, or in some aspects of it, may be encouraged to amplify or to correct this brief sketch. A.G. Pugsley

The Structurals Comforts Fund was established in 1940 to supply such comforts as it was possible to obtain to our serving members, so that they might be reminded that their colleagues in the Institution have them constantly in their thoughts.

It is unfortunate that Mr. Gordon followed the statement at the top of page 376, that the Arithmetical Procedure of Prof. Newmark is accurate for M/I diagrams made up of straight lines or parabolic arcs with a detailed exposition of the procedure on page 378, which is only applicable to M/I diagrams which vary uniformly from one end of a span to the other, as it is liable to make readers think that the simple working of page 378 is applicable to all the cases covered by the original statement, which is far from the case. As a matter of fact the procedure outlined is not truly correct, as, for instance, the first and last ordinates of span AB line (a) page 378 should really be 1/36 and 35/36. The first introduices an error varying linearly from A to B, and the other is not used subsequently, so that the final linear correction of line (e) results in correct values in line (f). If the figures were used to compute slopes, as at the top of page 389, the error pould still be present.