ON STEAM-SHIP PERFORMANCE. 193 



Tables 3 and 4. This is the more valuable, as the returns of seven trials on 

 the measured mile are given with it. 



Your Committee are aware that several officers are conducting a series of 

 experiments under various conditions, which it is their intention to report to 

 your Association, through this Committee, on their return home. 



The Log-book, compiled by your Committee, is also being filled up by the 

 same officers, with a similar object. 



Your Committee have met with great success in their applications to ship- 

 owners, engineers, and builders for information respecting the sea performances 

 of merchant vessels. In no case have they met with a refusal to supply all 

 the data in their possession, and your Committee have reason to believe that 

 before long the records kept on the voyages will be amplified, and the data 

 thus obtained be published periodically by shipowners themselves. 



The thanks of the Committee are especially due to the Peninsular and 

 Oriental Company, to the London and North-Western Company, to the 

 Pacific Steam Navigation Company, to the City of Dublin Steam Packet 

 Company, to Messrs. Morrison and Co. of Newcastle, to Messrs. Penn and 

 Sons, the Thames Shipbuilding Company, Messrs. R. Napier and Son, Messrs. 

 Fawcett, Preston and Co., and Messrs. J. and W. Dudgeon. 



The Peninsular and Oriental Company freely offered their books for in- 

 spection, and placed the logs of their vessels ' Candia,' ' Ceylon,' ' Columbia,' 

 ' Delta,' ' Nubia,' and ' Pera,' in the hands of the Committee, to make any 

 extracts they deemed useful. 



Copies of voyages from Southampton to Alexandria, and from Aden to 

 Calcutta, and return of those vessels respectively, were taken, and the average 

 performances worked out. They are given in the Table of Merchant Vessels 

 (Appendix, Table 5). 



The London and North- Western Railway Company have furnished your 

 Committee with information of especial value, viz., the trial performance and 

 ordinary working performance of one of their vessels, the ' Cambria,' under 

 two conditions — the first as originally constructed, the second after being 

 lengthened 40 feet. Data of this description are precisely those required to 

 enable the naval architect to judge what are the qualities which constitute a 

 good vessel, and assist him in designing vessels possessed of high speed, 

 great capacity, limited draught of water, economy of power, and all the 

 qualities which constitute good sea-going ships, with much greater certainty 

 than heretofore. 



In the same table (No. 5) your Committee have thought fit to repeat a 

 somewhat similar return, given in their last Report, viz., a Table, &c., show- 

 ing the Trial Performance of the steam vessels ' Lima ' and ' Bogota ' when 

 fitted with single-cylinder engines, and after being refitted with double- 

 cyHnder engines ; also the sea performances of the same vessels under both 

 these conditions of machinery, and on the same sea-service. 



These returns, therefore, show the difference of performance of a vessel 

 with the same machinery but lengthened in her hull, and of two vessels with 

 the hull a constant, but with entirely different engines. 



_A glance at the column showing the consumption of coals in each case 

 will at once demonstrate the importance of the subject in a commercial point 

 of view. 



The London and North- Western Company have likewise furnished returns 

 of the speed and consumption of coal of their express and cargo boats, under 

 regulated conditions of time, pressure, and expansion, from January 1 to De- 

 cember 31, 1860 (Ai^peudix, Table 6). Similar returns for 1858 and 1859 

 are contained in the two former Reports of this Committee, and show the 

 regularity with which the service has been conducted. 



1861. 



