on Steam-Boats. 247 
degree of heat have different degrees of expansion, I thought it 
by no means a perfect and secure boiler. 
Had you any opportunity of observing the boiler, so as to form 
a judgement whether the cast-iron end was of sufficient strength 
to resist the pressure of the steam ?—I had no such opportunity. 
Had you any opportunity of observing when you were aboard, 
whether the steam was properly regulated ?—Yes ; I found that 
the safety-valve was pressed down by a lever, and when I first 
went on board, the steam was so high as to require the weight 
near the extreme end of the lever. My opinion respecting the 
insecurity of high pressure engines is not formed in consequence 
of the late-accident; for on the 3d of March last, having occasion 
to write to a Mr. Rawlinson, who had applied to me to con- 
struct a steam-packet for his friends, I concluded my letter with 
these words ; “ Is it intended to have a low or a high pressure 
engine? if the latter, I should decline having any concern in the 
business, as they are attended with danger in any situation, but 
especially so in a steam-packet, where the lives of all on board 
would be at the mercy of the sobriety and attention of the en- 
gine worker.” 
You mean of course to say, that they would be so if no pre- 
cautions other than those which have hitherto been in use were 
adopted to prevent it?—Certainly; 1 allude to high pressure 
engines, as they have been hitherto usually arranged. 
[Mr. George Dodd was again called in on a future day, and 
examined. ] 
Can you inform the Committee, or give them any general 
idea, what amount of capital is vested in steam-boats ?—I have 
been on board and am well acquainted with twenty; and know 
that there are more than forty in Great Britain; many have cost 
5000/. others 60U0/. and one on the Thames above 10,0001. ; 
I consider a fair average to be 3500/. each, making the vested 
capital 140,000/. Most of them are fitted up with peculiar ele- 
gance and accommodation, and the furniture and decorations 
alone form an expensive item; they are also very expensive to 
maintain, especially on the ‘Thames, by reason of the great cost 
of coal. They are most numerous on the Clyde, where they 
have been productive of essential benefit to the general commerce 
and traflic of Glasgow, Port Glasgow, Greenock, and the neigh- 
bouring country. ; 
What description of engines and boilers have the steam- boats, 
you personally know, or with which you are personally ac- 
quainted ?—All I know have low pressure condensing engines, 
and wrought sheet-iron riveted boilers, except the remaining 
steam-boats between Yarmouth and Norwich, and one in Hol- 
Jand, built at Yarmouth ; and they are high pressure engines. 
Mr. 
