Withy. — On the Stabillti/ of Shijjs. 653 



angled triangles of Nature. Without that, it would have at 

 the best the interest of a game of chess, which is itself a 

 process of necessary reasoning resting on hypotheses, but 

 on hypotheses which have nothing in Nature that corresponds 

 to them. 



Art. LXVI. — TJie Stability of Shi2)s : its Principles made 

 clear by Models and Diagrams. 



By E. Withy. 



[Bead before the Auckland Institute, 10th August, 1891.] 

 Plates L., LI. 



Eather more than twenty years ago public attention was very 

 forcibly called to the question of the stability of ships by the 

 capsizing of H.M.S. "Captain," and the consequent loss of 

 nearly five hundred lives. Not only was the shock produced 

 by this event very great, but the surprise that was generally 

 expressed nearly equalled the shock. The vessel had made 

 two successful preliminary cruises, and was proceeding on a 

 third in company with other men-of-war. She had crossed the 

 Bay of Biscay, and was standing up well to her canvas, when 

 the breeze freshening caused her to list rather more than 

 before, and, without any warning, she steadily settled down, 

 turned completely over, and went to the bottom. Less than 

 twenty men, I believe, escaped and reported the occurrence 

 substantially as I have given it. 



Another stimulus was given within the last ten years by 

 the capsizing of the steamer " Daphne " on the occasion of 

 her launch, and the consequent drowning of a number of work- 

 men. 



On each occasion an exhaustive inquiry was instituted as 

 to the form and construction of the ships. Naval architects 

 were employed to make such calculations as the existing know- 

 ledge of the subject of stability rendered possible. I think I 

 am correct in saying that no addition was thus made to the 

 best information on the subject ; but a result of very great im- 

 portance did follow, and that was, that an enormous impetus 

 was given to the study of the question, and a conviction be- 

 came wide-spread that, after all, true theory must be more 

 allied with practice tlian had been the custom. 



Both vessels were built by eminent private firms of the 

 first rank, the former on the Mersey and the latter on the 

 Clyde ; yet it was evident that these firms did not consider it 



