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evaporation and the consequent rainfall, have a very beneficial effect on the
dry regions in the interior of the continent, and in some cases have almost
superseded irrigation. The windmill and dynamo thus utilize bleak
mountain-tops that, till their discovery, seemed to be but indifferent
successes in Dame Nature's domain. The electricity generated by these, in
connection with that obtained by waterfalls, tidal dynamos, thunderstorms,
chemical action, and slow-moving quadruple-expansion steam engines, provides
the power required to run our electric ships and water-spiders, railways, and
stationary and portable motors, for heating the cables laid along the bottom
of our canals to prevent their freezing in winter, and for almost every
conceivable purpose. Sometimes a man has a windmill on his roof for light and
heat; then, the harder the wintry blasts may blow the brighter and warmer
becomes the house, the current passing through a storage battery to make it
more steady. The operation of our ordinary electric railways is very simple:
the current is
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taken from an overhead, side, or underneath wire, directly through the air,
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ABC Amber Palm Converter, http://www.processtext.com/abcpalm.html
without the intervention of a trolley, and the fast cars, for they are no
longer run in trains, make five miles a minute. The entire weight of each car
being used for its own traction, it can ascend very steep grades, and can
attain high speed or stop very quickly.
"Another form is the magnetic railway, on which the cars are wedge-shaped at
both ends, and moved by huge magnets weighing four thousand tons each, placed
fifty miles apart. On passing a magnet, the nature of the electricity charging
a car is automatically changed from positive to negative, or vice versa
, to that of the magnet just passed, so that it repels while the next
attracts. The successive magnets are charged oppositely, the sections being
divided halfway between by insulators, the nature of the electricity in each
section being governed by the charge in the magnet. To prevent one kind of
electricity from uniting with and neutralizing that in the next section by
passing through the car at the moment of transit, there is a "dead stretch" of
fifty yards with rails not charged at all between the sections. This change in
the nature of the electricity is repeated automatically
file:///C|/2590%20Sci-Fi%20and%20Fantasy%2...20in%20Other%20Worlds%20-%20JJ%20
Astor.htm (26 of 221) [12/28/2004 12:32:22 AM]
A Journey in Other Worlds
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every fifty miles, and obviates the necessity of revolving machinery, the
rails aiding communication.
Magnetism being practically as instantaneous as gravitation, the only
limitations to speed are the electrical pressure at the magnets, the
resistance of the air, and the danger of the wheels bursting from centrifugal
force. The first can seemingly be increased without limit; the atmospheric
resistance is about to be reduced by running the cars hermetically sealed
through a partial vacuum in a steel and toughened glass tube; while the third
has been removed indefinitely by the use of galvanized aluminum, which bears
about the same relation to ordinary aluminum that steel does to iron, and
which has twice the tensile strength and but one third the weight of steel. In
some cases the rails are made turned in, so that it would be impossible for a
car to leave the track without the road-bed's being totally demolished; but in
most cases this is found to be unnecessary, for no through line has a curve on
its vast stretches with a radius of less than half a mile. Rails, one hundred
and sixty pounds to the yard, are set in grooved steel ties, which in turn are
held by a concrete road-bed consisting of broken stone and cement, making
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spreading rails and loose ballast impossible. A large increase in capital was
necessary for these improvements, the elimination of curves being the most
laborious part, requiring bridges, cuttings, and embankments that dwarf the
Pyramids and would have made the ancient Pharaohs open their eyes; but with
the low rate of interest on bonds, the slight cost of power, and great
increase in business, the venture was a success, and we are now in sight of
further advances that will enable a traveller in a high latitude moving west
to keep pace with the sun, and, should he wish it, to have unending day."
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Chapter 1.5
DR. CORTLANDT'S HISTORY CONTINUED.
"In marine transportation we have two methods, one for freight and another for
passengers. The old-
fashioned deeply immersed ship has not changed radically from the steam and
sailing vessels of the last century, except that electricity has superseded [ Pobierz całość w formacie PDF ]

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