118 Transactions of the Royal Canadian Institute 



many purposes, such as cooking utensils. A number of years ago in 

 the United States when buildijig some torpedo boats, we sought to save 

 weight by the use of aluminum in various places where strength was 

 not important. We found however that the aluminum sooner or later 

 in the presence of salt water or even salt air degenerated into a chalky 

 substance. Curiously enough a recent alloy of aluminum, known as 

 duralumin, seems quite resistant to destructive forces which soon dis- 

 integrate pure aluminum. 



The science of physics has played a particularly prominent part in 

 men-of-war of late years. The branch of optics alone has given us the 

 theories of and made practicable the various range-finding instruments 

 which, in conjunction with the fire-control systems, make possible the 

 accurate firing of guns and torpedoes. Even acoustics is a branch in- 

 volved in connection with all vessels. They all require the trans- 

 mission of intelligence by means of sound. Other methods of transmis- 

 sion of intelligence and orders are used however as it is essential for men 

 of-war that the systems of communication be adequate and so arranged 

 that they will not fail us by probable damage from the enemy, or break 

 down in the midst of the noise and copfubion of battle, or because of the 

 high mental tension at such times of the personnel using them. 



The sciences of ph^^siolo^y, medicine and hygiene seem alien to 

 the naval architect but cannot be ignored in connection with the con- 

 structionof any ship. During war and under war conditions it is some- 

 times necessary to operate with little regard to hygiene, but during the 

 long years of peace a large battleship must be the healthful and as far as 

 possible the happy home for anywhere from 1,000 to 1,500 men. At 

 best these men live under somewhat crowded conditions, and what we 

 term in the Navy "berthing and messing facilities," which correspond to 

 the housing, and feeding conditions in ordinary life must be based on 

 the most modern scientific principles. 



The ventilation of a large man-of-war involves many problems other 

 than those of hygiene. Such vessels are made up of a large number of 

 compartments or cells of which the mjajority are watertight and airtight. 

 Some of them are never occupied by human beings except for such pur- 

 poses as cleaning and painting. Double bottom compartments and oil 

 fuel tanks are in this class. Some compartment's such as storerooms and 

 magazines are occupied at intervals but not continuously. Fire rooms 

 and engine rooms and dynamo rooms are occupied continuously in the 

 service of the ship and need to be cooled as well as ventilated. While 

 we use as living quarters every part of the ship which receives natural 

 daylight and ventilation, it is still necessary for men to live in spaces 

 where they must rely upon artificial light and ventilation. Our ven- 



