The British Empire Exhibition at Wembley

V.-CONCRETES AT BASIC WATER CONTENT. Several tests were made at basic water content using 25 F.A. mixed in three proportions, the ratios of cement to mixed aggregate by bulk being approximately 1:8, 1:5, and 1:2 1/2 or 3. J. Singleton-Green

As announced in our last issue we propose, in conjunction with the Bennett College, Sheffield, to publish each month a simple problem in Graphic Statics, for the best solution of which the Governor of the Bennett College will award a prize of 10s. In allotting points, neatness will receive the same consideration as accuracy.

One of the most versatile and utilitarian buliding products developed in America during the last fifteen years is the concrete stave. This unit is in reality a small flat slab, usually about 30 inches long, 10 to 14 inches wide and 1 1/2 to 2 1/2 inches thick, but it is known as a stave because it is laid up end on end, usually on construction such as tanks, where it replaces the wood stave. A.J.R. Curtis