WITH DRY HEAT. 211 



capable of being adapted to high pressure or any 

 other form of apparatus whatever. 



By the use of this invention there is no fear of 

 danger, and I have been surprised, considering 

 the objections which have been raised to various 

 apph cations of steam, and the frequent instances 

 of explosions^ even when boilers have been pro- 

 nounced by Government inspectors perfectly safe, 

 that an apparatus operating so perfectly as the one 

 I exhibit should be so misunderstood. On the 

 contrary, with any application of steam there is a 

 presence of danger, and I may say the fact is 

 made notorious by the accidents daily occurring 

 in the use of steam in every form ; were it not so, 

 how is it that with thermometers registering a 

 degree of heat which indicates perfect safety, and 

 even the safety-valves themselves, known to be 

 perfectly free from any additional weight what' 

 ever, that explosions under such favourable 

 auspices continually take place ? Engineers, 

 though unable to explain this melancholy phe- 

 nomenon, have resorted to a beautiful but not 

 wholly harmless expedient, that of placing plugs 

 of lead at the bottom of the boiler, so that when 

 the supply of water should be below the working 

 point, the heat, coming up to 500° or 600°, melts 

 out the lead, which allows the steam to pass off 

 without exploding or doing any material damage. 

 But with this apparatus there is no pressure. 

 You may put your hand within a few inches of 



p 2 



