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Steam Navigation.

about forty-five pounds.—Thinks it very possibleto lock up one of the valves, which may be soconstructed as not to be liable to accidents fromexplosion.—Did not see any reason why, in anysituation whatever, the use of an engine should belimited to the low pressure, or that which isusually called the condensing engine. — Con-ceived that cast iron could be made much strongerthan wrought iron, with less difficulty; some ofthe cast-iron boilers being made two inches thick;and to make a wrought-iron boiler equally strongas that, would be very difficult to be accomplishedby w ? orkmen.—Had known of no accident withhigh-pressure steam and cast-iron boilers; buthad known an accident happen working withBoulton and Watt’s low-pressure engine, whichwas on the 28 th of November, 1811 , in WhealAbraham mine; a wrought-iron boiler, workingw r ith low-pressure steam, exploded there, andscalded six men, three of whom died of the burns?they received in the course of a week afterwards.—Did not recollect any instance in which awrought-iron boiler exploded, so as that any per-sons were killed by the fragments.—Did not con-ceive that water could issue to any great distancefrom a high-pressure boiler, as it must soon besteam.—Had never known any persons scaldedby the steam or the water issuing from a high-pressure boiler ; but remembered many instancesof persons being scalded from the same cause bya low-pressure engine, only one of which came