ON STEAM-SHIP PERFORMANCE. 197 



Mail Steam Packet Company, to the Pacific Steam Navigation Company, to 

 the London and North-Western Railway Company, to Messrs. Inglis Bro- 

 thers, Messrs. Randolph and Elder, Messrs. Caird and Co., Messrs. R. Na- 

 pier and Sons, and to Captain Walker, of the Board of Trade. 



Captain W T alker very obligingly placed at the service of the Committee 

 some of the books in which the vessels registered and surveyed by the Board 

 of Trade are recorded, and your Committee are in possession of copies of the 

 entries of 51 vessels, varying from 600 to 2000 tons register and upwards, 

 registered in the ports of London, Liverpool, Southampton, and Glasgow, 

 during 1858. These have formed a very useful guide in leading to a selec- 

 tion of vessels from which to obtain the particulars requisite for comparison. 



Your Committee have been in communication also with the French and 

 American ambassadors, with a view to obtaining the statistics of perform- 

 ance of their respective navies; and, after referring the matter to their home 

 Governments, the Committee have received the assurance of their willingness 

 to cooperate. 



Your Committee, being precluded by the terms of their appointment from 

 discussing theories, or attempting to deduce laws, have, nevertheless, thought 

 it not inconsistent to prepare a table of ratios based on the indicated horse- 

 power, and showing the ratio between that element, as developed on the 

 measured mile, and the grate, the tube, and other heating surfaces of the 

 boilers producing it; also, between the grate and heating surfaces, and be. 

 tween the indicated horse-power and the coal consumed. The Committee 

 regret that this important item, the coal, is not more frequently recorded, 

 very few private trials making any note of it ; and in no instance brought 

 under the notice of the Committee, have the Admiralty officers made known 

 this element, so necessary for ascertaining the efficiency of the boilers (for 

 Table of Ratios, see Appendix IV. Table 1). 



The following is a general summary of the result of the Committee's 

 labours during the past session. They have obtained : — 



1. Returns of 353 trials by 216 of Her Majesty's vessels of war during the 

 years 1857, 1858, and 1859, with about 900 (898) diagrams taken during 

 the trials in 1859; also notes, by the officers conducting the trials, of 

 observed facts. 



Of these trials, fifty-eight made by seventeen of the vessels, have been 

 selected by way of illustration, with the particulars of machinery obtained from 

 the makers, and arranged in a tabular form. 



iey, and ' Virago. 



1 his Table also comprises the two American vessels, < Niagara ' and ' Massa- 

 chusetts,' together with the British vessel ' Rattler,' introduced for compari- 

 son. 



2. Returns of 68 merchant vessels. 



Four diagrams taken during trials of the ' Atrato.' 



Scale of displacement of the 'Atrato.' 



Lines of ditto. 



Eight diagrams of the ' Shannon ' taken during trials. 



quil,' 'Undine,' ' Erminia,' 'Admiral,' 'Emerald,' and 'John Penn. 



The returns of the first four, belonging to the London and North- Western 



