86 Report of the Select Committee 
What is called the safety-valve had been improperly loaded 
and neglected?—-Yes, but that never need happen; the principle 
of steel-yards is to put a weight at the end, and if you put no more 
than that, it will answer its purpose ;—so with a steam-engine; 
it may be overloaded, and its effect destroyed. The next acci- 
dent happened, not from a fault of any body, but from an act of 
God; it was lightning, as was satisfactorily explained to the 
public, both by the passengers and those interested in the boat 5 
that was at Charleston in South Carolina; the pipe which carries 
the smoke up to the top attracted the lightning, and it went down 
and split the boiler. 
It was not considered as at all connected with the operation 
of the engine >No, not at all through negligence. A third ac- 
cident happened lately to the Powhattan ; she was not in opera- 
tion when it happened; they were out of fuel, they stopped their 
boat and lay still upon the water while they went after wood ; 
still however they kept up their fire, and the steam was high, and 
it exploded in that situation, there being no consumption of the 
steam as it accumulated. Those are the only accidents that 
ever happened, except such as have happened from vessels taking 
fire. 
Were those vessels high or low pressure engines ?—All low 
pressure engines. No accident has ever happened in America to 
a high pressure engine, either ina manufactory or out of it; and 
there are many engines used in the manufactories, and in flour- 
mills and saw-mills, constructed upon the plan of Oliver Evans, 
which act on the high pressure principle to 150 pounds an inch; 
he has worked 160, but 120 is his constant average. There is not 
an old woman in America that is ever frightened at all at a high 
pressure engine, any more than they now are at a cannon. There 
is a very large engine, about a forty-five horse power, at St. Sen- 
nati, on the Ohio River, which moves seven pair of stones in a 
flour-mill, a woollen manufactory, and a cotton manufactory 
seven stories high; it works upon the high pressure, and there 
are saw-mills and grist-mills at various places. 
What is the fuel ?—Wood in most places. - At Pittsburgh and 
on the Ohio River it is coal and wood; at Pittsburgh and at 
Weeling, and a hundred other places, there is fifty miles square 
a solid mass of coal; they drive the shaft horizontally into the 
hill, and the coal is abundant above their head in the mountains, 
as fine coal as any in the world; it is delivered at the houses of 
the inhabitants at sixteen bushels for a dollar. : 
Is the number of steam-boats now increasing in America ?— 
Very rapidly. 
Are those that are now constructing upon the high or the low 
pressure system?—-Upon both, because there are different in- 
terests 
