306 



Mr. Reed on the Form, Dimensions, 



[Mar. 19, 



sider the two substances identical. Treated with hydrate of potassium, 

 this nitrile is converted into an acid which M. Merz describes under the 

 name of naphthaline-carboxylic acid. The opinion expressed by this 

 chemist, that his acid might be identical with the one observed by myself, 

 I am inclined to adopt, although there are still some few discrepancies in 

 our observations to be elucidated. M. Merz states that the fusing-point 

 of his acid is at 140°, whilst the acid examined by myself fuses at 

 160". In order to remove, if possible, this discrepancy, I have, since 

 I saw M. Merz's paper, again and repeatedly taken the fusing-point of 

 menaphthoxylic acid, but always with the same result. Possibly the fusing- 

 point of the acid prepared by means of a sulphonaphthylate may be found 

 somewhat higher when the compound is carefully purified by repeated 

 crystallization from alcohol. 



II. " On the Relation of Form and Dimensions to Weight of 

 Material in the Construction of Iron-clad Ships.^^ By E. J. 

 Reed, Chief Constructor of the Navy. Comnaunicated by Prof. 

 G. G. Stokes, Sec. R.S. Received March 3, 1868. 



(Abstract.) 



The object of the Paper is to show that the proportion of length to 

 breadth in a ship, and the form of her water-lines, should be made in a 

 very great degree dependent upon the weight of the material of which her 

 hull is to be constructed— that an armour-plated ship, for example, should 

 be made of very different proportions and form from those of a ship with- 

 out armour, and that as the extent and thickness of the armour to be 

 carried by a ship are increased the proportions of length to breadth should 

 be diminished, and the water-lines increased in fulness. 



It is highly desirable that this subject should receive the attention of 

 men of science, not only because it bears most directly upon both the cost 

 and the efficiency of future iron-clad fleets, but also because it opens up 

 a theoretical question which has hitherto, I believe, received absolutely no 

 consideration from scientific writers upon the forms and resistances of 

 ships, viz. the manner in which the weight of the material composing the 

 hull should influence the form. Prior to the design of the * Bellerophon/ 

 the forms of ships were determined in complete disregard of this considera- 

 tion ; and even the most recent works upon the subject incite the naval 

 architect to aim always at approaching the form of least resistance. The 

 investigations given in the Paper show, however, that the adoption of a 

 form of least resistance, or of small comparative resistance, may, in fact, 

 lead to a lavish outlay upon our ships, and to a great sacrifice of efficiency ; 

 while, on the other hand, the adoption of a form of greater resistance would 

 contribute in certain classes of ships to greater economy and to superior 

 efficiency. 



