68 Explosion of a Steam-Engine Builci: 



the premises completely destroyed and in ruins, the windows 

 of the adjoining houses entirely broken, and a building nearly 

 fifty yards from the scene of destruction set on fire by pieces of 

 io-nited fuel falling upon its roof. 



^ The boiler employed in this manufactory was eight feet 

 long, four feet broad, and five feet deep, and had recently 

 undergone a thorough repair ; it was connected with machi- 

 nery requiring steam of great expansive force for its move- 

 ments, and Saturday the 29th ult. was the first time of using 

 it since the repairs. 



The steam was speedily raised in such a very powerful 

 manner, that, as I have since learned, the boiler was perceived 

 to have an oscillating movement for a considerable time : — 

 when the steam had attained this state, and while Mr. Boult 

 with four of his men were anxiously looking on, the boiler sud- 

 denly burst, and in a moment spread desolation all around. 



The situation of tlie persons present now became truly de- 

 plorable — buried in the falling ruins of the building, and scalded 

 in a shocking manner : prompt assistance was however ob- 

 tained, and every effort that surgical skill could command, 

 was brought into action for the alleviation of the sufferings of 

 the unfortunate individuals: but alas ! four out of the five per- 

 sons present on this occasion (amongst whom Mr. Boult him- 

 self) have fallen victims to the explosion. 



Upon examinmg the boiler, I found the bottom completely 

 torn away on one side fi'om the seat of the vessel, and forced 

 into the ash-pit; the plates of iron, half-inch in thickness, 

 forming the bottom of the boiler, were twisted from the convex 

 to the concave form, and the two surfaces of the severed plates 

 presented comparatively smooth faces, with little or no ap- 

 pearance of raggedness. 



Most unfortunately in the present case, neither the respected 

 proprietor of the engine, nor indeed any of his men, had suf- 

 ficient knowledge of the force of highly compressed steam, to 

 render the working of the engine safe in their hands. In 

 the instance before us no doubt is entertained that the safety 

 valve was overloaded; the boiler, on ordinary occasions, 

 worked at a pressure of thirty pounds to the square inch; but 

 with boldness the most fatal, it was on this occasion exposed 

 (there is reason to believe) to a pressure of upwards of one 

 hundred pounds. And here let us pause for a moment to in- 

 quire whether the present mode of constructing steam valves 

 be entitletl to unlimited confidence ? In my opinion, no valve 

 ought to be deemed safe imless made perfectly independent of 

 the most careful workman that ever existed. The very pos- 

 sibility of a safety valve being by awj means ' over-weighted' 



implies 



