Structures in Aluminium

The CHAIRMAY (Dr. Oscar Faber, O.B.E., M.Inst.C.E., Vice-president), who regarded the paper as one of the most interesting ever presented to the Institution, proposed a hearty vote of thanks to the author for the extraordinarily interesting collection of photographs he had shown, as well as for the paper itself, and for the admirable way in which he had presented it.

It may be stated in a general way that, for a given nature of sand and a given quality of cement agglutinant the strength of the resulting concrete increases when its compactness increases. The lack of compactness may be due in part to bad granulometry, which is a question into which it is not proposed to enter specifically in this paper; assuming that the best granulometric composition of the inert, component has been attained, lack of compactness may still be due to the fact that full advantage is not taken of the possibilities presented by the composition of the mixture, that air cavities remain in the concrete, either through the presence of mechanically enclosed air bubbles, or through the gradual evaporation of superfluous water. T.J. Gueritte

The rapid growth of aerial transportation during the last ten years so admirably illustrated by the activities of Imperial Airways Ltd., and particularly the wide interest shown in the spectacular flight of Scott and Black from Mildenhall Aerodrome to Melbourne in two and a half days, have focussed public attention on the urgent necessity for providing adequate landing fields and aerodromes in this country. It is noteworthy that H.R.H. The Prince of Wales remarked at the recent Airport Conference, “Take care of the wheels and the wings will take care of themselves.” The aeronautical engineer has indeed done his share, and such enormous strides have been made in aircraft design that the operational speed of machines is approaching 200 m.p.h. If, therefore, it is true that “time is money,” here is economy with a vengeance. H.E. Brooke-Bradley