1825.] Plans of Ship3 in the British Navy, 32S 



a theory of Tessels from facts ; in addition to this, it would 

 afford correct official data for computation, and a navy which 

 costs 15,000,000/. sterling in every ten years would have its 

 construction founded on accurate estimates. I have ardently 

 pursued the study of the subject since, and in consequence do 

 not hesitate to state, that the government would save by it more 

 than the value which the execution of the plan would cost, 

 besides raising the dock yard service of the navy in scientific 

 competition with that of foreign powers. 



Col. Beaufoy and Mr. G. Harvey, of Plymouth, a few months 

 ago, in the Annals of Fhilosophi/, recommended a course of 

 experiments on resistance as the only means of extending our 

 knowledge of the scientific construction of ships. So strongly did 

 the latter assert the necessity of it, that he said " all was darkness 

 and uncertainty without it." It is my opinion, however, from 

 the little advantage hitherto derived from such courses, and the 

 difficulties of applying what knowledge could be obtained from 

 them to ships, that it is by no means a promising track of pur- 

 suit for a theory of vessels. The maximum of the power of 

 carrying sail must be united with the minimum of resistance, and 

 both with the weight of hull, pitching, and rolling qualities, &c. 

 When we consider the paucity of knowledge applicable to ship- 

 building, arising from the efforts of the splendid constellation of 

 genius that pursued the subject of the resistance of fluids in the 

 French Academy for twenty years (from 1770 to 1790); the 

 results of the ardent application of the Society for the Encou- 

 ragement of Naval Architecture, in making 10,000 experiments 

 for the same branch of knowledge ; together with the failures of 

 several other distinguished bodies and individuals : — our expec- 

 tation from the institution of another course of experiments on 

 resistance ought not to be very sanguine. To obtain the theory 

 of resistance seems to be more in the department of a national 

 learned body, as the resolution of a fine physical problem in 

 mathematics, rather than as a work to be depended on for 

 improvement in ship-building. 



If we can ascertain the force or moving power of the sails 

 acting at the point velique or resultant of the resistance, we may 

 note 100 formal expernnents on resistance in every ship that 

 goes to sea ; and this I believe it possible to obtain to a very 

 near degree of approximation, probably as nearly as in any regu- 

 lar experiment on a model. 



Again, if we have the resistance at a given velocity of a ship, 

 which may be obtained by swinging a ship in a stream, and 

 measuring the pull, we have the power of the sail acting at its 

 centre of effort when this ship sails on the ocean with such a 

 celerity as the given motion. 



Ships sail on different lines of bearing ; therefore the best 

 form for resistance in one direction is not likely to be that in the 



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