122 Report of the House of Commons on Steam-Boais. 



be built with a scantling for & sailing-vessel of twice that ton- 

 nage. — Mr. PwOgcr Fisher says, " There has been, in my opi- 

 nion, a great improvement made in the strength of steam-vessels 

 built here (Liverpool) lately; that is, by carrying the frame 

 timbers uji so as to form the projection of the sides, and then 

 regularly planked up solid as any other part of the vessel, by 

 which means the}' aie much safer." — Mr. Brunei, Avhen asked 

 whether he v/ould recommend a steam-boat to be built much 

 stronger than usual for sailing-vessels? gave the Committee 

 to understand, that great weight would be injurious, by lessen- 

 ing the buoyancy of the vessel ; but Captain Rogers's eA'idence 

 corroborates the opinions of the other witnesses, and seems to 

 show that this inconvenience does not follov/ : — " Q. Have you 

 found those two vessels (the Holyhead steam-boats) equally 

 buoyant with any other you have sailed in? — A. Yes. — 

 Q. Has the great weight of their timbers, and other materials, 

 diminished their speed? — A. No ; I think it rather gives them 

 speed against a sea. — Q. Then the inconvenience anticipated 

 from the mode of constructing these vessels has not taken place ? 

 — A. No; it has not." — Mr. George Henr^r Freeling says, 

 " I have attempted to gain some information about every' 

 steam- vessel which has been built; and I am convinced these 

 vessels (the Holyhead packets) will do what no other vessels 

 can do, — they will go to sea in weather when nothing else can ; 

 I attribute that not only to the machinery, but to the great 

 weight of the hull ; a lighter vessel in a heavy sea would be 

 checked ; but these vessels have from their weight a momen- 

 tum so great that it carries them on when a lighter vessel 

 would be checked ; the weight acts as a fly-wheel." — " I have 

 the authority of Mr. Lang of the Navy Board for stating that, 

 with the exception of the Discovery ships, there are no vessels 

 so strong." 



in. Machinery. 



The steam-engine, employed on board ships, is as yet a 

 much less perfect machine than when it is used on land ; the 

 height of the cylinder is nearly one half less ; the power is 

 thereby cramped by short strokes, which are incalculably bad. 

 In this way there is a great loss of power, as the vis incrtice is 

 to be overcome on every stroke ; more frequent alternations 

 are necessary of the beam, the piston and the valves, which 

 occasion more wear, and more friction than wliere the cylin- 

 ders are made longer. There is also a considerable loss of 

 power in converting the alternate motion of the piston into 

 the rotary motion of the jiaddles. 



The engines, as now used at sea, want some contrivance 

 to enable them to bear with the irregularity of the pressure on 



them : 



