yAS Sir B. Redwood on Romance of Petroleum [June 7, 



relatively small area bold enoiig-h oil to compensate for the reduction 

 in volume of the contents of the tanl<s resulting from decrease in 

 temperature, and conversely afford adequate stoi'age room for oil 

 expelled owin«^ to increase in temperature. If the main tanks were 

 not kept completely full, dangerous oscillation of the cargo would 

 take place when the ship was rolling, and as an additional precaution 

 the tanks are fitted with an amidship fore-and-aft bulkhead, as shown. 

 The coffer-dam, at the after-end of the series of tanks, is formed by 

 a double bulkhead, and it may be filled with water so as to prevent 

 any oil which may leak from the adjacent tank from finding its way 

 aft. At first the conservatism of shipbuilders, or perhaps the artistic 

 instincts of the nautical man, led to the engines being placed in the 

 usual position, amidships. This, however, necessitated the provision 

 of a second coffer-dam, as well as an oil-tight tunnel from the 

 screw-shaft, extending through the after-tanks, and the propelling 

 machinery is now usually placed aft, as shown. The pumps for dis- 

 charging the cargo are an important part of the equipment. The 

 pump-room is here shown below deck immediately forward of the 

 machinery space. The diameter of the piping connected with the 

 tanks, and the capacity of the pumps, are now such that a cargo of 

 10,000 tons can be discharged in twelve hours. The more modern 

 vessels are fitted with mechanical ventilating appliances by means of 

 wiiich air can be forced into or drawn from any oil-compartment, and 

 an accumulation of vapour prevented. 



Besides these tank-ships, tank-barges of the description known as 

 " dumb," therefore requiring to be towed, are largely used, and are 

 often of great size. We are all familiar with tlie appearance of the 

 petroleum tank-wagons on our railways and in our streets. By means 

 of these, and the ocean-transport already described, a very large 

 proportion of the products mide in the principal petroleum refineries 

 of the world reaches the wholesale or retail distributor, and in 

 many cases the consumer, without being placed in packages of any 

 description. 



But for the disabilities imposed on me by the Ofiicial Secrets Act, 

 the stringent regulations made under the Defence' of the Realm Act, 

 and the Censor, the subject could have been presented in a more 

 entertaining manner; but T hope I have been able to deal with it in 

 such a way as to justify the title which I had the temerity to select. 



[B.R.] 



