192 REPORT — 1861. 



table of certain of Her Majesty's vessels, seventeen In number, had been con- 

 structed, containing the results of the best trials as conducted by the Govern- 

 ment officers, and that it had been forwarded to the Admiralty with the 

 request that the additional particulars of the hull and machinery' might be filled 

 in. The table, however, did not arrive in time to be inserted in their Report. 



Your Committee have great pleasure in being now enabled to lay it before 

 your Association in the state it has been received from the Admiralty. 

 (Appendix, Table 1.) They would remark in connexion with this return, 

 that it appears that the authorities have not been in the habit of recording 

 either the quantity of coals consumed or the evaporation of water, and they 

 have made application to the Admiralty that in future these desiderata may 

 be obtained. 



In compliance with the terms of the resolution appointing the Committee, 

 viz., " That the attention of the Committee be also directed to obtaining infor- 

 mation respecting the performance of vessels under sail, with a view to com- 

 paring the results of the two powers of wind and steam," your Committee 

 have to state that hitherto they have been unable to obtain such comparisons 

 in the case of merchant vessels, but in the Table given in Appendix, Table 2, 

 particulars of one of H.M. vessels are recorded under three conditions, viz., 

 under steam alone, under sail alone, and under steam and sail combined, 

 and of two under the two latter conditions only. 



These are especially useful, as they show the effects produced by powers 

 brought to bear upon the hulls of vessels under the same conditions as to 

 draft and trim, but differently applied. 



In endeavouring to collect this Information from officers in H.M.'s service, 

 the Committee were desirous that the application should be made with the 

 concurrence of the Admiralty, and a circular was accordingly issued to a se- 

 lected number of officers, accompanied by a form, which they were requested 

 to fill up and return. At the request of the Admiralty, copies of these docu- 

 ments were submitted for their Inspection. 



The circular stated that the Committee had apprized the Admiralty of the 

 Committee's proposal to communicate with such captains and engineers of 

 H.M.'s vessels as might be disposed to assist the British Association in obtain- 

 Ino- facts for scientific calculations relating to the performance of ships at sea. 



The form proposed was as simple as was consistent with the object of ob- 

 taining data necessary for calculation, and the Committee conceived that the 

 time required to fill up such forms would not interfere with the duties of the 

 respective officers. It also stated that the Committee Invited the co-opera- 

 tion of officers for the benefit of science alone, and that one of the fundamental 

 rules laid down by the Association In directing their labours was as follows ; — 



" The object of the Committee is to make public recorded facts, through 

 the medium of the Association, which, being accessible to the public in that 

 manner, will bring the greatest amount of science to the solution of the diffi- 

 culties now existing to the improvement of the forms of vessels and the qua- 

 lities of marine engines. They will especially endeavour to guard against 

 Information so furnished to them being used in any other way." 



Your Committee Issued the Circular and Form of Return (see Appendix, 

 p. 198) to upwards of 200 of H.M.'s captains In commission, and to their chief 

 engineers through the captains. 



Numerous replies have been received promising returns ; but the distance 

 at which most of the vessels are stationed, namely, China, the East Indies, 

 and America, has precluded our receiving such particulars in time for this 

 Report. Returns, however, of seven vessels have been received, six of which 

 are given In Appendix, Table 2 ; and the seventh vessel, the ' Victor Emman- 

 uel,' being returned in a different form, is given separately in Appendix, 



