A journey in other worlds - A romance of the future by John Jacob Astor
page 43 of 339 (12%)
page 43 of 339 (12%)
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considerable bulk with weight. South of Hatteras, where stones
are scarce, the sand dredged from parts of the channel was filled into the crib, the surface of which has a concave metallic cover, a trough of still water being often the best barrier against the passage of waves. This double coast-line has been a great benefit, and propelled vessels of moderate draught can range in smooth water, carrying very full loads, from Labrador to the Orinoco. The exits are, of course, protected by a line of cribbing a few hundred feet to seaward. "The rocks have been removed from all channels about New York and other commercial centres, while the shallow places have been dredged to a uniform depth. This diminishes the dangers of navigation and considerably decreases the speed with which the tides rush through. Where the obstructions consisted of reefs surrounded by deep water, their removal with explosives was easy, the shattered fragments being allowed to sink to the bottom and remain there beneath the danger line. "Many other great works have also been completed. The canals at Nicaragua have been in operation many years, it having been found best to have several sizes of locks, and to use the large ones only for the passage of large vessels. The improved Erie and Champlain Canals also enable ships four hundred feet long to reach New York from the Great Lakes via the Hudson River. "For flying, we have an aeroplane that came in when we devised a suitable motor power. This is obtained from very light paper-cell batteries that combine some qualities of the primary and secondary type, since they must first be charged from a |
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