SAFETY OF LIFE FROM FIRE AT SEA. 39 



shipboard. Commercial sulphur is burned in a specially designed furnace con- 

 nected to the holds by a double line of piping. Air is drawn from the holds through 

 one pipe by a high-powered blower and discharged into the furnace, where it is 

 converted into sulphurous gas, which in turn is forced back into the hold through 

 the second line of piping. 



Thus oxygen is replaced by non-combustion supporting gas. When the gas 

 contents have reached a certain percentage the burning sulphur is cut off, and the 

 gas-laden air in the hold is circulated by the same machine through a cooler which 

 forms its base, and fresh air is gradually admitted. The cooling-down process can 

 be observed and regulated at the machine. 



So-called fire indicators are fitted to the machine with connections to the chart 

 room. In operation air is drawn from the various holds and any rise in tempera- 

 ture is indicated. It is claimed that this machine is now used- on vessels of 2,000,000 

 tons gross tonnage. 



The gas has been considered objectionable since it causes asphyxiation, an at- 

 mosphere containing only 3 per cent of the gas being fatal to life. This is the same 

 suffocating gas of which one gets a whiff from the burning of an old-fashioned 

 brimstone or sulphur match, and it is liable to be of greater efficiency in quickly 

 extinguishing the breathing power of human beings anywhere in the vicinity than 

 in extinguishing fires. It is also said to be injurious to certain kinds of merchan- 

 dise since it is a powerful bleaching agent. 



The use of nitrogen gas has also been experimented with. It is made by forc- 

 ing air through a confined burning body, whereby instantaneously the nitrogen and 

 oxygen of the air are disengaged and free nitrogen with an occasional trace of car- 

 bon dioxide gas given off. 



The boilers of steam vessels at sea are constantly producing and discharging 

 through the smoke-stack a similar mixture. The apparatus which has been designed 

 to utilize these gases for fire extinguishment consists of a blower with suction piped 

 to the uptake flue over the boiler ; a cooler made of a coil of pipe water-jacketed and 

 placed in the suction pipe so that the gases may pass freely into the usual pipe 

 distribution system. Valves are provided on pipes to cabins, etc., in which people 

 are apt to be present, so that the gases can be discharged as the rooms are vacated. 



The records of the patent offices are overloaded with hundreds of devices for ap- 

 plying various gases for extinguishing fire on shipboard, which it must be instantly 

 recognized as utterly impracticable by all who are familiar with the art of fire extin- 

 guishment or with conditions on shipboard. 



Automatic Sprinklers. — In the foregoing I have briefly outlined the history of 

 fire protection on shipboard and described present general practice. The auto- 

 matic sprinkler, which has been in use particularly in factories during the past thirty 

 years, has proven to be a great conserver of life as well as property. The records 

 of the Associated Factory Mutual Fire Insurance Companies show that since 1874 

 there were only five lives lost by fires in about 3,000 factories thus protected. There 

 are employed in these factories 1,500,000 people. In all the factories equipped with 



