Naval Architecture and Ship Building 119 



tilating pipes and apparatus must not only supply the crew with ade- 

 quate air but must be planned so that they will not allow water to pass 

 from a compartment flooded by damage in action to another still intact. 



To insure efficiency in battle, the design must take careful cognizance 

 of what medical science has ascertained as to the limitations oi human 

 enduj'ance when working at high pressure under adverse conditions. 

 In addition to the general hygienic considerations to be taken into account 

 throughout the whole ship, a large first-class ship at present carries a 

 completely equipped medical establishment or hospital, including 

 operating rooms, isolation ward for contagious diseases, special exam- 

 ining and treatment rooms, dental facilities, etc. During late years 

 there has been developed a specialized type of hospital ship proper, which 

 accompanies the fleet and furnishes it with hospital facilities essentially 

 equal to those found in the best hospitals ashore. 



Electrical science pervades a modern man-of-war from stem to stern. 

 On our latest capital ships electrical apparatus is used to drive the ship, 

 to steer the ship, to train and fire the guns, to hoist the anchor, to raise 

 the ammunition, to turn the turrets, to ventilate the ship, and fpr an 

 infinite nuVnber of minor purposes. 180,000 H. P. = Electric power of 

 a city of 700,000. 



During the last ten years or so the growth of wireless telegraphic 

 methods of communication — radio we c^ll it for shortness — has been 

 such as to establish virtually a new branch of science. Radio has found 

 its major use so far in the communication between ships at sea with other 

 ships and with the land. I need not enlarge upon its value in this field 

 but desire simply to call your attention in passing to the fact that useful 

 and used as it is on land, radio telegraphy has been developed mainly 

 for use on shipboard. 



I hope Ihave said enough to make clear the fact that practically 

 every branch of science and engineering (which is applied science) must 

 or can enter into the design of the great ships of the present day. 



The great advantage of the scientific development of naval archi- 

 tecture which has been so notable during the last fifty years or so, is 

 that we are enabled to progress by long steps rather than short. The 

 naval architect seldom evolves a ship out of his own consciousness, as 

 the German philosopher undertook to do with the elephant. The first 

 estimate or approximation of a ship to meet certain requirements must 

 be based largely on previous practice and experience. Before the devel- 

 opment of scientific naval architecture in its modern sense, this resulted 

 in rather slow step-by-step progress from one ship to another. By 

 applying scientific analysis and methods to the results of the past, 

 however, we are now able to make our steps much greater, so that 



