The Salt Lake herald. [volume] (Salt Lake City [Utah]) 1870-1909, 1908-07-13
SOME LATE SCIENCE NOTES.
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Tie sailing distance from New York 10
Punta Arenas, AZ the southern end oi
South America via the Panama canal.
will be ST miles less than by the route
which IS al present followed by vessels
between those points.
The cost of the railroads OF the United
States is rlaced ct Sl2,Vs ,O0o,00 for the
.l3G01 miles Tor which the figures are
available.
North America has. speaking in round
terms. 261GJG miles of railway, Of which
225o01 are found in the United States.
Europe as a whole has 10000 miles. or
SEQ miles less than those in the Unite
States alone. Asia has 5000 miles, Arr
ca l7.CCG and Australia and the adjacent
islands OF Oceanic HOO
Under the encoura cement of the electric
power supply companies there has re-
Gently been a cry great Improvement in
the electric vacuum cleaning apparatus.
and there can now b. found on the mar
ket such devices all the way from light.
portable apparatus weighing only seventy
pounds. using a. one-sixth horsepower
motor and costing about SIS. IN TO a
large stationary pant employing motors
from five horsepower up ana costing
many hundreds of dollars. The machines
range ali the way from those producing
very small vacuum aod moving = con-
siderable volume of air up To others main
tanning fiiteen-inch vacuum, which viii
pull the dust clear through an ordinary
rug. The smaller machines are rather
new on the market as yet. and it is diff
cult to predict how extensively. they will
be used. II is not unreasonable to SUP
pose that if once rug is thoroughly
cleaned il can be kept clean thereafter by
frequent applications Of light suction. and
for miscellaneous dIsting low vacuum is
well suited There thus should be a good
field for the small, portable apparatus
which can be used i'm every house where
electric service is available.
The familiar taDe telegraph which has
been u~ed for many years in stock brok-
ers' offices and Other public places for
the transmission CT news intelligence OF
general interest is rapidly being supplant-
ed by another Ssytem by which the mes
saSes are printed on a sheet. line after
line This is great Improvement over
the old style and much time is saved to
persons who may have occasion to make
use of the instrument. In the case of the
newer method the messages are torn off
in sheets of handy length. and posted 1T
a convenient place. whereas with the tame
considerable time must be lost in going
over the great string of tape which accu-
mulates in the course OF a few hours An
installation Of this character has been re-
Gently made il the capitol. where several
OF the more important committee rooms
are supplied with such receiving stations
and members who happen TO be detained
in these rooms during the sessions of con-
greSs are enabled to keep fully informed
as to the proceedings of the body The
proceedings of both branches of the body
are reported and the members have found
this device or much value.
In Dubuque. la. there is a recently en-
acted law which requires that the view Of
the interior of all saloons shall be unob-
structed so that those inside shall be in
full view at all times. but the law has
been cleveriy circumvented by the saloon
keepers. who. while complying with the
terms of the law literally. have al the
same time secured the desired privacy
by making use of a coupe of strong cleo
trio lights backed with reflectors so that
any one attempting to peer into the place
is blinded by the rays of light. This ruse
is to he tested in the courts as il is con-
tended by some that IL is a clear VIOLA
ton of the law. for the strong rays of the
lamp are just as much OF a curtain as
one made of fabric.
The very latest practice in block sig
mailing. interlocking and automatic train
stopping is to be found in operation in the
tunnels of the Hudson & Manhattan rail-
road. which were recently opened under
the Hudson river. On steam railroads
block signal sections average 900 feet. or
two signals per mile: on the express
tracks of the New York subway the dis
lance is 500 feet, or nearly seven signals
per mile. In the Hudson tunnels the sig
nal distance is only 367 feet-or more than
fourteen signals per mile The signals arc
three indications-"proceed" indicated nv
green light: proceed with Caution vel
low light: stop" red light As the CON
sequences of a train passing a signal in
the stop position may be disastrous. a
device for automatically stopping such
train is used al each signal This con-
ssts OF two movable short arms or trims
placed alongside each rail When tha
signal is in the stop" position these arms
are raised to engage with the trigger of
a valve in the airbrake pipe of the train
releasing the air and setting the brakes
Each car is equipped with two of these
valves-one at each end and o.. Opposita
sides of the car When the signal moves
again to the proceed" position the cleo
trio motor moves these train-stop arms
out of stop position. thus perrntttino
the train to pass without setting th
brakes. the arms being returned 10 stnn
position by gravity after the train has
entered the block.