SfX WILLIAM SIEMENS, F.R.S. 367 



/// t/M discussion of th* Paper 

 " ON STEEL FOR SHIPBUILDING," by B. MARTELL, 



DR. CHARLES W. SIEMENS * said, with reference to the observa- 

 ti<>n that fell from Mr. Reed, as to the difficulty of rolliug steel 

 plates to dimensions that would present a reduction of weight 

 n|;i:il to 20 per cent., T would mention that when the material 

 for the Iris and the Mercury were ordered from the Landore 

 Company, a wish was expressed by the authorities that the weights 

 of the plates should in no case exceed those specified, but that it 

 would be desirable to make those plates perhaps 2 per cent, less in 

 weight than would follow from the calculation. I believe the 

 Landore Company acted strictly up to that, and that the total 

 weight of the material supplied was just 2 per cent, below that 

 calculated, showing that there really is no difficulty in working by 

 weight instead of dimensions. I would suggest that it would be a 

 far more rational thing to order the plates by weight per square 

 foot, rather than by vulgar fractions of an inch thickness. With 

 regard to riveting, I, for one, would strongly advocate steel rivets 

 in preference to iron. It is true that at Pembroke the experiments 

 tend rather to show that no material advantage would be gained 

 by the employment of steel rivets, but at that time the question 

 was hardly sufficiently understood. Now steel has been produced 

 which I think answers its purpose perfectly, and reduces the risk 

 of rivet heads falling off to a minimum. I may mention that at 

 another Institution, Mr. Boyd, the engineer of the Slipway Com- 

 pany, will read a paper to-day giving the result of the construction 

 of several steel boilers in which steel rivets were employed, and he 

 states in that paper that not a single rivet gave way or gave any 

 trouble whatever in the manipulation, showing that with a little 

 care difficulties that have been complained of, such as overheating, 

 may be overcome. The advantage of steel riveting over iron is 

 not only in the rivet itself, but it is in a great measure in the 

 plate, which has to be cut away to a much less extent, and thus 



* Excerpt Transactions of the Institute of Naval Architects, Vol. XIX. 1878, 

 p. 29. 



