COMPRESSED GASES 91 



on the works, not in public use has since occurred in the 

 north of England. 



No oxygen ought ever to be pumped into any but the usual 

 black bottles ; and no hydrogen or house-gas into any other 

 than red bottles. These are the two colours accepted by the 

 trade and general consent. I also insist very strongly, that 

 no pumpers have any right to fill up a bottle, without first 

 seeing that all pressure is let off. These rules give safety, and 

 no other rules do so ; as to little contrivances sold for cus- 

 tomers to ' test ' their gas, a large proportion of operators have 

 not knowledge enough to use such things. If an explosion 

 occurred, and fatal results followed, and it were proved that 

 the pumpers had broken the first of the rules just mentioned, 

 the culprits ought to be, and I believe would be, held guilty of 

 manslaughter. Since the explosion just referred to, all firms 

 of real standing now act upon both ; and while it is necessary to 

 point out where any neglect has caused accident, it may be 

 well to repeat, that not a single accident has yet happened to 

 any user of the gas in England up to this date, out of thou- 

 sands of cylinders. It is, indeed, difficult to understand how 

 any accident can happen without criminal carelessness on the 

 part of the firm supplying the gas ; the few accidents which 

 have occurred ' in the trade ' itself, having pointed out the 

 only sources of danger very clearly. The ' mixture ' which 

 might possibly occur with bags, if carelessly handled, is by the 

 high pressure of the cylinders rendered, with them, practically 

 impossible. 



CHAPTER VII 



THE OXY-ETHER AND HYDRO-CARBON LIGHTS 



50. The Oxy-ether Light. For many years lamps have 

 occasionally been employed in laboratories which burnt the 

 vapour of some volatile fluid in place of gas ; and recently such 



