a journey in other worlds-第9节

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shall　owe　much　of　the　success　of　the　great　experiment　on　Mother
Earth　now　about　to　be　tried。
　　　
〃Another　change　that　came　in　with　a　rush　upon　the　discovery　of　a
battery　with　insignificant　weight；　compact　form；　and　great
capacity；　was　the　substitution　of　electricity　for　animal　power
for　the　movement　of　all　vehicles。　　This；　of　necessity　brought　in
good　roads；　the　results　obtainable　on　such　being　so　much　greater
than　on　bad　ones　that　a　universal　demand　for　them　arose。　　This
was　in　a　sense　cumulative；　since　the　better　the　streets　and　roads
became；　the　greater　the　inducement　to　have　an　electric　carriage。　
The　work　of　opening　up　the　country　far　and　near；　by　straightening
and　improving　existing　roads；　and　laying　out　new　ones　that
combine　the　solidity　of　the　Appian　Way　with　the　smoothness　of
modern　asphalt；　was　largely　done　by　convicts；　working　under　the
direction　of　State　and　Government　engineers。　　Every　State
contained　a　horde　of　these　unprofitable　boarders；　who；　as　they
formerly　worked；　interfered　with　honest　labour；　and　when　idle　got
into　trouble。　　City　streets　had　been　paved　by　the　municipality；
country　roads　attended　to　by　the　farmers；　usually　very
unscientifically。　　Here　was　a　field　in　which　convict　labour　would
not　compete；　and　an　important　work　could　be　done。　　When　once　this
was　made　the　law；　every　year　showed　improvement；　while　the
convicts　had　useful　and　healthful　occupation。
　　　
〃The　electric　phaetons；　as　those　for　high　speed　are　called；　have
three　and　four　wheels；　and　weigh；　including　battery　and　motor；
five　hundred　to　four　thousand　pounds。　　With　hollow　but　immensely
strong　galvanically　treated　aluminum　frames　and　pneumatic　or
cushion　tires；　they　run　at　thirty…five　and　forty　miles　an　hour　on
country　roads；　and　attain　a　speed　over　forty　on　city　streets；　and
can　maintain　this　rate　without　recharging　for　several　days。　　They
can　therefore　roam　over　the　roads　of　the　entire　hemisphere；　from
the　fertile　valley　of　the　Peace　and　grey　shores　of　Hudson　Bay；　to
beautiful　Lake　Nicaragua；　the　River　Plate；　and　Patagonia；
improving　man　by　bringing　him　close　to　Nature；　while　they　combine
the　sensations　of　coasting　with　the　interest　of　seeing　the
country　well。
　　　
〃To　recharge　the　batteries；　which　can　be　done　in　almost　every
town　and　village；　two　copper　pins　attached　to　insulated　copper
wires　are　shoved　into　smooth…bored　holes。　　These　drop　out　of
themselves　by　fusing　a　small　lead　ribbon；　owing　to　the　increased
resistance；　when　the　acid　in　the　batteries　begins　to　'boil；'
though　there　is；　of　course；　but　little　heat　in　this；　the　function
of　charging　being　merely　to　bring　about　the　condition　in　which
part　of　the　limestone　can　be　consumed；　the　batteries　themselves；
when　in　constant　use；　requiring　to　be　renewed　about　once　a　month。　
A　handle　at　the　box　seat　turns　on　any　part　of　the　attainable
current；　for　either　going　ahead　or　reversing；　there　being　six　or
eight　degrees　of　speed　for　both　directions；　while　the　steering　is
done　with　a　small　wheel。
　　　
〃Light　but　powerful　batteries　and　motors　have　also　been　fitted　on
bicycles；　which　can　act　either　as　auxiliaries　for　hill…climbing
or　in　case　of　head　wind；　or　they　can　propel　the　machine
altogether。
　　　
〃Gradually　the　width　of　the　streets　became　insufficient　for　the
traffic；　although　the　elimination　of　horses　and　the　consequent
increase　in　speed　greatly　augmented　their　carrying　capacity；
until　recently　a　new　system　came　in。　　The　whole　width　of　the
avenues　and　streets　in　the　business　parts　of　the　city；　including
the　former　sidewalks；　is　given　up　to　wheel　traffic；　an　iron　ridge
extending　along　the　exact　centre　to　compel　vehicles　to　keep　to
the　right。　　Strips　of　nickel　painted　white；　and　showing　a　bright
phosphorescence　at　night；　are　let　into　the　metal　pavement　flush
with　the　surface；　and　run　parallel　to　this　ridge　at　distances　of
ten　to　fifteen　feet；　dividing　each　half　of　the　avenue　into　four
or　five　sections；　their　width　increasing　as　they　approach　the
middle。　　All　trucks　or　drays　moving　at　less　than　seven　miles　an
hour　are　obliged　to　keep　in　the　section　nearest　the　building
line；　those　running　between　seven　and　fifteen　in　the　next；
fifteen　to　twenty…five　in　the　third；　twenty…five　to　thirty…five
in　the　fourth；　and　everything　faster　than　that　in　the　section
next　the　ridge；　unless　the　avenue　or　street　is　wide　enough　for
further　subdivisions。　　If　it　is　wide　enough　for　only　four　or
less；　the　fastest　vehicles　must　keep　next　the　middle；　and　limit
their　speed　to　the　rate　allowed　in　that　section；　which　is　marked
at　every　crossing　in　white　letters　sufficiently　large　for　him
that　runs　to　read。　　It　is　therefore　only　in　the　wide
thoroughfares　that　very　high　speed　can　be　attained。　　In　addition
to　the　crank　that　corresponds　to　a　throttle；　there　is　a　gauge　on
every　vehicle；　which　shows　its　exact　speed　in　miles　per　hour；　by
gearing　operated　by　the　revolutions　of　the　wheels。
　　　
〃The　policemen　on　duty　also　have　instantaneous　kodaks　mounted　on
tripods；　which　show　the　position　of　any　carriage　at　half…　and
quarter…second　intervals；　by　which　it　is　easy　to　ascertain　the
exact　speed；　should　the　officers　be　unable　to　judge　it　by　the
eye；　so　there　is　no　danger　of　a　vehicle's　speed　exceeding　that
allowed　in　the　section　in　which　it　happens　to　be；　neither　can　a
slow　one　remain　on　the　fast　lines。
　　　
〃Of　course；　to　make　such　high　speed　for　ordinary　carriages
possible；　a　perfect　pavement　became　a　sine　qua　non。　　We　have
secured　this　by　the　half…inch　sheet　of　steel　spread　over　a
carefully　laid　surface　of　asphalt；　with　but　little　bevel；　and
though　this　might　be　slippery　for　horses'　feet；　it　never
seriously　affects　our　wheels。　　There　being　nothing　harder　than
the　rubber　ties　of　comparatively　light　drays　upon　itfor　the
heavy　traffic　is　carried　by　electric　railways　under　groundit
will　practically　never　wear　out。
　　　
〃With　the　application　of　steel　to　the　entire　surface；　car…tracks
became　unnecessary；　ordinary　wheels　answering　as　well　as　those
with　flanges；　so　that　no　new　tracks　were　laid；　and　finally　the
car　companies　tore　up　the　existing　ones；　selling　them　in　many
instances　to　the　municipalities　as　old　iron。　　Our　streets　also
need　but　little　cleaning；　neither　is　the　surface　continually
indented；　as　the　old　cobble…stones　and　Belgian　blocks　were；　by
the　pounding　of　the　horses'　feet；　so　that　the　substitution　of
electricity　for　animal　power　has　done　much　to　solve　the　problem
of　attractive　streets。
　　　
〃Scarcely　a　ton　of　coal　comes　to　Manhattan　Island　or　its　vicinity
in　a　year。　　Very　little　of　it　leaves　the　mines；　at　the　mouths　of
which　it　is　converted　into　electricity　and　sent　to　the　points　of
consumption　by　wire；　where　it　is　employed　for　all　uses　to　which
fuel　was　put；　and　many　others。　　Consequently　there　is　no　smoke；
and　the　streets　are　not　encumbered　with　coal…carts；　the　entire
width　being　given　up　to　carriages；　etc。　　The　ground　floors　in　the
business　parts　are　used　for　large　warehouses；　trucks　running　in
to　load　and　unload。　　Pedestrians　therefore　have　sidewalks　level
with　the　second　story；　consisting　of　glass　floors　let　into
aluminum　frames；　while　all　street　crossings　are　made　on　bridges。　
Private　houses　have　a　front　door　opening　on　the　　sidewalk；　and
another　on　the　ground　level；　so　that　ladies　paying　visits　or
leaving　cards　can　do　so　in　carriages。　　In　business　streets　the
second　story　is　used　for　shops。　　In　place　of　steel　covering；
country　roads　have　a　thick　coating　of　cement　and　asphalt　over　a
foundation　of　crushed　stone；　giving　a　capital　surface；　and　have　a
width　of　thirty…three　feet　（two　rods）　in　thinly　settled
districts；　to　sixty…six　feet　（four　rods）　where　the　population　is
greater。　　All　are　planted　with　shade　and　fruit　trees；　while　the
wide　driveways　have　one　or　two　broad　sidewalks。　　The　same　rule　of
making　the　slow…moving　vehicles　keep　near　the　outside　prevails；
though　the　rate　of　increase　in　speed　on　approaching　the　middle　is
more　rapid　than　in　cities；　and　there　is　usually　no　dividing
ridge。　　On　reaching　the　top　of　a　long　and　steep　hill；　if　we　do
not　wish　to　coast；　we　convert　the　motors　into　dynamos；　while
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