a journey in other worlds-第11章
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running at full speed; and so change the kinetic energy of the
descent into potential in our batteries。 This twentieth…century
stage…coaching is one of the delights to which we are heirs;
though horses are still used by those that prefer them。
We have been much aided in our material progress by the facility
with which we obtain the metals。 It was observed; some time ago;
that when artesian and oil wells had reached a considerable
depth; what appeared to be drops of lead and antimony came up
with the stream。 It finally occurred to a well…borer that if he
could make his drill hard enough and get it down far enough;
keeping it cool by solidified carbonic acid during the
proceeding; he would reach a point at which most of the metals
would be viscous; if not actually molten; and on being freed from
the pressure of the crust they would expand; and reach the
surface in a stream。 This experiment he performed near the hot
geysers in Yellowstone Park; and what was his delight; on
reaching a depth scarcely half a mile beyond his usual stopping…
place; to be rewarded by a stream of metal that heralded its
approach by a loud explosion and a great rush of superheated
steam! It ran for a month; completely filling the bed of a
small; dried…up river; and when it did stop there were ten
million tons in sight。 This proved the feasibility of the
scheme; and; though many subsequent attempts were less
successful; we have learned by experience where it is best to
drill; and can now obtain almost any metal we wish。
〃'Magnetic eyes' are of great use to miners and Civil engineers。
These instruments are something like the mariner's compass; with
the sensitiveness enormously increased by galvanic currents。 The
'eye;' as it were; sees what substances are underground; and at
what distances。 It also shows how many people are in an
adjoining roomthrough the magnetic properties of the iron in
their bloodwhether they are moving; and in what directions and
at what speed they go。 In connection with the phonograph and
concealed by draperies; it is useful to detectives; who; through
a registering attachment; can obtain a record of everything said
and done。
〃Our political system remains with but little change。 Each State
has still two United States Senators; though the population
represented by each representative has been greatly increased; so
that the Senate has grown numerically much more than the House。
It is the duty of each member of Congress to understand the
conditions existing in every other member's State or district;
and the country's interest always precedes that of party。 We
have a comprehensive examination system in the civil service; and
every officeholder; except members of the Cabinet; retains his
office while efficiently performing his duty; without regard to
politics。 The President can also be re…elected any number of
times。 The Cabinet members; as formerly; usually remain in
office while he does; and appear regularly in Congress to defend
their measures。
〃The really rapid transit lines in New York are underground; and
have six tracks; two being used for freight。 At all stations the
local tracks rise several feet towards the street and slope off
in both directions; while the express tracks do this only at
stations at which the faster trains stop。 This gives the
passengers a shorter distance to descend or rise in the
elevators; and the ascent before the stations aids the brakes in
stopping; while the drop helps the motors to start the trains
quickly in getting away。
〃Photography has also made great strides; and there is now no
difficulty in reproducing exactly the colours of the object
taken。
〃Telephones have been so improved that one person can speak in
his natural voice with another in any part of the globe; the wire
that enables him to hear also showing him the face of the speaker
though he be at the antipodes。 All telephone wires being
underground and kept by themselves; they are not interfered with
by any high…tension electric…light or power wires; thunderstorms;
or anything else。
〃Rain…making is another subject removed from the uncertainties;
and has become an absolute science。 We produce clouds by
explosions in the atmosphere's heights and by surface air forced
by blowers through large pipes up the side of a mountain or
natural elevation and there discharged through an opening in the
top of a tower built on the highest part。 The aeriduct is
incased in a poor heat…conductor; so that the air retains its
warmth until discharged; when it is cooled by expansion and the
surrounding cold air。 Condensation takes place and soon serves
to start a rain。
〃Yet; until the earth's axis is straightened; we must be more or
less dependent on the eccentricities of the weather; with
extremes of heat and cold; droughts and floods; which last are of
course largely the result of several months' moisture held on the
ground in the form of snow; the congestion being relieved
suddenly by the warm spring rains。
〃Medicine and surgery have kept pace with other
improvementsinoculation and antiseptics; as already seen;
rendering most of the germ diseases and formerly dreaded
epidemics impotent; while through the potency of electrical
affinity we form wholesome food…products rapidly; instead of
having to wait for their production by Nature's slow processes。
〃The metric system; now universal; superseded the old…fashioned
arbitrary standards; so prolific of mistakes and confusion; about
a century ago。
〃English; as we have seen; is already the language of 600;000;000
people; and the number is constantly increasing through its
adoption by the numerous races of India; where; even before the
close of the last century; it was about as important as Latin
during the greatness of Rome; and by the fact that the Spanish
and Portuguese elements in Mexico and Central and South America
show a constant tendency to die out; much as the population of
Spain fell from 30;000;000 to 17;000;000 during the nineteenth
century。 As this goes on; in the Western hemisphere; the places
left vacant are gradually filled by the more progressive
Anglo…Saxons; so that it looks as if the study of ethnology in
the future would be very simple。
〃The people with cultivation and leisure; whose number is
increasing relatively to the population at each generation; spend
much more of their year in the country than formerly; where they
have large and well…cultivated country seats; parts of which are
also preserved for game。 This growing custom on the part of
society; in addition to being of great advantage to the
out…of…town districts; has done much to save the forests and
preserve some forms of game that would otherwise; like the
buffalo; have become extinct。
〃In astronomy we have also made tremendous strides。 The
old…fashioned double…convex lens used in telescopes became so
heavy as its size grew; that it bent perceptibly from its own
weight; when pointed at the zenith; distorting the vision; while
when it was used upon a star near the horizon; though the glass
on edge kept its shape; there was too much atmosphere between it
and the observed object for successful study。 Our recent
telescopes have; therefore; concave plate…glass mirrors; twenty
metres in diameter; like those used for converging the sun's rays
in solar engines; but with curves more mathematically exact;
which collect an immense amount of light and focus it on a
sensitive plate or on the eye of the observer; whose back is
turned to the object he is studying。 An electrical field also
plays an important part; the electricity being as great an aid to
light as in the telephone it is to sound。 With these placed
generally on high mountain peaks; beyond the reach of clouds; we
have enormously increased the number of visible stars; though
there are still probably boundless regions that we cannot see。
These telescopes have several hundred times the power of the
largest lenses of the nineteenth century; and apparently bring
Mars and Jupiter; when in opposition; within one thousand and ten
thousand miles; respectively; so that we study their ph