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their length being 16 feet 4 inches, and the ends nearly hemis pherical at the back, and flat at the front. They had two oval furnace tubes running to the back of the boiler and returning to the funnel at the front by means of a flattened flue of very questionable shape, while the load on the safety-valve was 181b. Both boilers gave way at the bottom, rending longitudinally from one end to the other, when the shells opened out and were blown upwards to a considerable distance. At the same time the sides of the vessel were blown out, and the whole sunk with all hands on board. Added to this, the debris was shot in every direction, and dwelling-houses in the neighbour hood invaded by a shower of missiles, a fire shovel being thrown into the window of one, a piece of plate on to the roof of another, fragments of the deck and spars on to a third, and so on. The cause of the explosion was simple in the extreme. The boilers had been so neglected that the plates at the bottom had been allowed to become wasted away by external corrosion till nearly eaten through, probably by the wash of the blige water. In consequence of this they burst from simple weakness, the most decayed boiler going off first, and by its shock leading to the rupture and consequent explosion of the other. The evidence at the inquest was of the most unsatisfactory character, though given by witnesses professedly scientific. Although a piece of plate, measuring 5 feet long, and reduced to the thickness of a knife-edge, which had been blown into a gentleman’s garden, was called attention to, yet the hacknied opinion was given that the explosion was due to shortness of water and red-hot plates, while the boiler was declared to have been a very good one, indeed, that the force of the explosion proved it to have been strong throughout, in addition to which, a Government officer, though his attention was specially called to the thin plates in the boiler, stated that such, though requiring to be treated with great care, would not cause an explosion, though they might a leak, and propounded the theory that explosions were generally due to superheated steam and the introduction of cold water. Palpable as were the evidences of corroded plates, the jury came to no decision whatever as to the cause of the explosion, but merely returned as their verdict that “ the deaths were caused by the explosion of a boiler on board a steam tug.” Such a verdict, affording no suggestions for the prevention of similar catastrophes in the future, could scarcely have been satisfactory to those whose houses had been invaded by the fragments of the exploded boiler. It must be clear that such inquiries must be perfectly useless as far as the prevention of steam-boiler explosions is concerned. Coroners’ inquests, however, might be of the utmost value if a competent investigation were made, and the truth plainly spoken, and if the juries, instead of confining themselves to the stereotyped verdict of “Accidental death,” would, whenever - the circumstances call for it, return for their verdict “ Six men blown to pieces by the explosion of an old worn-out boiler, totally unfit for use.” It may be added that another boiler explosion had occurred on board this same steam tug some time before when in another port, on which occasion three men were killed, and the captain lost one of his eyes. No. 17 explosion, by which two persons were killed and three others injured, occurred at a building yard. Disastrous as were the results of this explosion, yet the boiler was a very small one, being only 4 feet 10 inches long, 2 feet 2 inches in diameter, and made of plates originally one- eighth or three-sixteenths of an inch in thickness. It was cylindrical in construction, with cambered ends, and had no furnace tube, but was fired externally. Though the age of the boiler could not be exactly ascertained, it appears that it was an old one, and had been purchased second-hand a few days before the explosion, at a sale, for £11 15s., including the brickwork, engine, and piping. It had been described on the auction bills as a “capital” boiler, but the boiler-maker, who repaired it shortly after purchase, spoke of it at the inquest as inferior, very thin, and much worn, and that there did not seem to be any nature left in the iron, while this view was corroborated by other witnesses. On setting the boiler to work it was not found to be satisfactory, and the owner stated “ it was all leaks, and would not drive the saws sufficiently to cut anything.” The day of the explosion was the first time of getting the boiler at all into work, and it appears that after running the engine a short time with the safety-valve screwed down to 151b., and finding there was not sufficient power to drive the saws satis factorily, the valve was further screwed down to 251b. or 301b. Shortly after this the explosion occurred, when the boiler was severed into four fragments, all of which were thrown from their original seat, one of them to a distance of 30 yards, in addition to which the chimney was levelled to the ground, while the son of the owner, and a plumber who had been called in to set the boiler and engine to rights, were both killed. Three of the rents started from the manhole, which measured 1-H inches by 12j inches, and was not strengthened as it should have been by a substantial mouthpiece. The estimates of pressure just given were only taken from, the index on the spring balance with which the safety-valve lever was loaded, and depended for their accuracy on the correctness of the spring, and the proportions of the lever. These could not be verified after the explosion, as the parts were completely destroyed; while in addition, as'there was no stop-ferrule to the safety-valve, if the range of the spring balance was a limited one, the valve may have been locked down on to the solid, as frequently explained in reporting on previous explosions, but it is now impossible to say what the pressure of steam was at the time of the explosion. Though this boiler was no doubt considerably weakened by thinning of the plates from wear and tear, yet the explosion is attributed mainly to the manhole’s being unguarded, while at the same time it may be pointed out that it was not safe to render the boiler entirely dependent on a single safety-valve loaded with a spring balance, especially since it was not fitted with a stop ferrule, so that this explosion must rank among those due to defective boiler equipment. No. 18 explosion, by which two men lost their lives, occurred on board a tug-boat propelled by paddles, and driven by a pair of grasshopper engines and a couple of boilers. The boilers were about three years old, and the boat had just been under going repairs, and was on its trial trip to test their completeness when the explosion occurred. The boilers were cylindrical in the shell, with two internal furnaces, and measured 1.3 feet 5 inches in length, by 7 feet 2 inches in diameter, while the furnaces were of almost triangular shape, the outer sides being a portion of a flat circle struck from the centre of the boiler, so as to accord with the sweep of the shell, and thus forming portions of a circle of about 6 feet in diameter. The height of these furnaces was 2 feet 10 inches, the width on the top 2 feet 11 inches, the length 10 feet 10j inches, and the thickness of the plates barely five-sixteenths of an inch, while the load on the safety-valve was 22 lb. per square inch. The boiler that exploded was the one on the port side of the vessel, the left hand furnace of which collapsed, the curved side bulging inwards and rending at a transverse seam of rivets. The boiler was not moved from its place, but the contents of the boiler rushed out into the engine-room, killing the two firemen. One of them was standing just in front of the boiler and managed to creep into the starboard coal bunker, but his lungs were so injured from inhaling the hot steam that he died shortly after. The other fireman was thrown down and rolled underneath the side lever of one of the engines, which continued to work on for a short time after the explosion, each revolution driving the end of one of the rods into the poor fellow’s back, while his legs were smashed by the motion of the air pump. The cause of the explosion is clear. The curved side of the furnace-tube, though of so flat a circle as 6 feet in diameter, and made of plates barely five-sixteenths of an inch in thick ness, was not strengthened by any stays, as it should have been, though these might easily have been applied by passing short screwed bolts through the water space to connect it to the shell. A plate derives no strength from forming a segment of a circle unless the ends are firmly secured, otherwise it becomes an arch without an abutment. Such was the case with the sides of these furnaces. Had this boiler - been tested with water, and carefully guaged while under pressure, the movement of the sides would at once have displayed the weak ness to any competent observer. This explosion was clearly due to the malconstruction of the boiler, but the jury brought in the usual verdict of “ Accidental Death.” No. 19 explosion, by which two persons were killed, occurred at a colliery, and affords a further illustration of the treachery of plain cylindrical externally fired boilers, which has been so frequently pointed out in previous reports.