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Dear Sir,-The use of slab bases for stanchions has introduced new calculations. The placing of a more or less concentrated load in the centre of a slab brings to one’s mind the picture of the stanchion sinking and giving the slab a saucer-like shape. A slab will, under certain conditions and if resting on a homogeneous foundation behave as a beam: that is to say, it will tend to deflect along a line or lines parallel with one or other pair of sides. If a slab be weaker on one axis it will commence to deflect, take on a channel shape, and (however slight that deflection) become at once stiffened against deflection on the other axis. The weaker way being found, the appropriate formula can be applied. Arpossible case is shown in Figure 1. Here the slab is a uniformly loaded beam with cantilever extensions.
The gasometer erected for the Southern Oil Co., Ltd., at Trafford Park, Manchester, is, in. plates, as far as can be ascertained, the first all-welded gasometer in this country, and marks a distinct step forward in the advance of welding.
The CHAIRMAN (Major F. M. Du Plat-Taylor, M.Inst.C.E., M.I.Mech.E., President of the British Section of the Societe des Ingenieurs Civils de France), proposing a hearty vote of thanks to Mr. Gueritte- himself the designer of the largest reinforced concrete bridges in this country-for his very able paper, said that the facts which it contained were surprising, as was so often the case with papers read before the Societe. In this connection he recalled a paper which had been read a year or so previously, describing the manner in which a cast iron railway bridge had been converted into a reinforccd concrete bridge without interrupting traffic, the method adopted being to insert mild steel tension bars on the tension side and to concrete the whole thing, and this had proved to be satisfactory. Railway engineers who had attended the meeting at which that paper was read had been asked to discuss the paper, but they had been so amazed by the information it contained that they had declined because they felt unequal to it. The achievements describcd in the paper by Mr. Gueritte probably could never be repcated in England under present conditions, for engineers were too much hampered by regulations-not that regulations were harmful, provided they were revised continually in order that they might keep pace with the improvements effected in structural materials. In this country, however, regulations were not up to date. For example, the stresses allowed in ordinary structural steel here were lower than those applying in almost any other European country, which meant that British engineers had to use more materia1 than other engineers would use for similar duties.