THE CONQUEST OF NATURE 



that of the ordinary type of submarine boat that is, 

 cigar- shaped this effect being obtained by a curved 

 deck completely covering the place ordinarily occu- 

 pied by a flat deck. A wheel-house, like a battle- ship's 

 conning-tower, is placed well forward, supported on 

 steel beams some distance above the curved deck for 

 observation purposes; and engines, boilers, and coal 

 bunkers occupy a small space in the stern. The boat, 

 therefore, is mostly hold. 



But the "whale-backs" form only a small portion 

 of the ore-fleet. The ordinary type of boat conforms 

 more nearly to the shape of ocean boats, except that 

 the bridge, wheel-house, and engines are located as 

 in the whale-backs. The bows of these boats are 

 blunt, the desideratum in such craft being hull-ca- 

 pacity rather than speed. For sea- worthiness they 

 are equal to any ocean boats, as the battering waves 

 of Lake Superior are quite as powerful and even more 

 treacherous than those of the Atlantic or Pacific. Some 

 of these boats are five hundred feet long, equal to all 

 but the largest ocean vessels. Their coal-carrying 

 capacity is relatively small, since coaling stations are 

 numerous at various points on the journey, and every 

 available inch of space is utilized for the precious 

 iron ore. 



In order to facilitate loading, the decks are literally 

 honey-combed with hatches, some boats having fif- 

 teen or sixteen openings extending the width of the 

 deck. By this arrangement the time of loading is 

 reduced to a matter of a few hours, as a dozen chutes, 

 each discharging several tons of ore per minute, soon 



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