Issue 4

Mr. HAMANN, when introducing the paper, took the opportunity to express his gratitude to Mr. Robert Campbell, B.Sc.(Eng.), A.M.Inst.C.E., consulting engineer, of New Zealand, to whom he owed the knowledge he had gained of earthquake effects. Mr. Campbell was formerly Professor of Civil Engineering at Canterbury (N.Z.) University College, and was a member of the New Zealand Building Regulations Committee, which had issued a report in June, 1931, only four months after the disastrous earthquake which had occurred in New Zealand that year. The committee had been re-assembled, and Mr. Campbell was one of its two technical officers, Mr. Hamann added that he had gained knowledge of the subject during the period in which he had assisted Mr. Campbell.

THE bridge over the Seine at La Roche Guyon (Figure 1) constructed under the direction of the Service Vicinal de Seine-et-Oise aux Etablissements Roussiron de Paris has a, totaal length of 662 ft. 9 in. with a single span over the river of ,528 ft. 3 in. The rise of the arch is 75 ft. 5 in. S. Boussiron and N. Esquillan

Sir,-It has long been known that the modulus of elasticity in compression of concrete increases with the quality of the concrete and this has been recognised in the New Code.

MR. REYNOLDS said that in presenting these observations of the New Code of Practice for Reinforced Concrete, his sole interest in the subject was the very personal one of attempting to interpret as a practising engineer the Code's recommendations.

Author's Supplementary Remarks THE question of vibration is apparently exercising many minds at present, and since the time when my text was completed, further information has reached me from various quarters which enables me to add many items to the bibliography of the subject, such as was published in "Science et Industrie" of February, 1934, and to which I had referred our colleagues. This new list contains some fifty references, and is embodied as a note at the end of the discussion. It is not claimed that it is complete, but it is fairly up to date, and a good many new points have been brought out.