A frightful catastrophe happened yesterday week on board H.M.S. Thunderer,'
the sister-ship to the Devastation.' She had steamed out from Portsmouth to try her speed on the measured mile, and the stokers, of whom there were 130 on board, and of whom thirty were actually in the stoke-hole at work on the furnaces, were getting up steam, when a great ex- plosion of steam occurred, which blew out the end of one of the boilers, and scalded fifteen persons to death on the spot. Nine- teen more died the same day. Up to yesterday morning forty-one deaths had taken place, mostly after great suffering, as the result of the frightful injuries received, and thirty-six more have been more or less seriously injured, making a list of casualties of seventy-seven in all. The horrors of the first hours of anguish can hardly be con- ceived. The only compensation to the nation is the heroism which, in such cases, some persons always display, of whom the chief in this instance appears to have been Mr. Weeks, one of the engineers, who stopped both the engines, groped his way through the scalding steam to the valves, which he closed, and then rushed upon deck to get other men to volunteer with him to rescue the victims. Indeed, he appears to have saved the captain of the 'Thunderer,' Captain J. C. Wilson, himself, who, being in the engine-room at the time of the explosion, was at once enveloped in scalding steam, and could not have found his way to the upper deck, had not Mr. Weeks come upon him in his way to the stop-valves, and led him up. The precise cause of the explosion is not yet disclosed.