80 Steam Navigation.

would perform the same work as the other enginewith twenty.

Mr. Timothy Bramah, of Pimlico, Engineer ,called in and examined.

Did not think that a high-pressure engine,under any guard that could be applied to it, was asafe engine to use in a steam-boat.—Thoughtthat if a boiler was prepared to sustain one hun-dred pounds, and strained with a force equal totwo hundred pounds, it might afterwards, per-haps, break at forty, the straining having injuredit.—Apprehended that a boiler, upon a properconstruction, of wrought metal, might be triedwith a certain force, so small in comparison withthat pressure which it was intended to bear, asnot to incur any risk of being injured in theproof, and have a complete surplus of strength, soas to enable it to be afterwards used without anydanger in the use.—Would recommend the use oftwo safety-valves, one to lock up ; and to have itexamined once a week, or as often as might be ne-cessary, to see that its action was perfect.—Hadseen many cast-iron vessels burst. The wroughtiron generally tore and opened out, to admit ofthe fluid escaping; it was generally the fluidwhich did the mischief when the wrought ironwas used, and it was both the fluid and the mate-rials which did the mischief when the cast ironburst. The effect in cast metal was to carry the