Wood County reporter. [volume] (Grand Rapids [i.e. Wisconsin Rapids], Wis.) 1857-1923, 1893-03-23
PNEUMATIC TUBES ABROAD.
Their Extensive Use in London, Paris,
Vienna, and Berlin.

Their Extensive Use in London, Paris,
Vienna, and Berlin.
! Engineering Magazine: Pneumatic
tubes for local transmission of tele-
grams are now used in all the principal
cities of Great Britain At present
about 50 miles of such tubes are in
| operation, requiring an aggregate of
400 horsepower, and transmitting n
daily average of los, 900 messages Tor
| over 100000 annually. more than
half of these in London. The lengths
of tubes vary greatly; the average
length is about $50 yards; the greatest
single length in London is 1892 wards.
The tubes are of lead, laid in cast-iron
pipes, for protection, and are usually
of IA inches inner diameter: some
tubes of 1 II and some of three inches
inner diameter are used. AS a general
rule, with the same air pressure and
diameter of tube the speed varies in
versely as the length of the tube. In
tubes not over a mile long the usual
average speed is % to 80 miles an
hour. The carriers are of gutta-percha
covered with felt, with a buffer at the
front end, and an elastic band at the
back or open end to hold in the messag-
es. All ordinary carrier weighing 2 "a
ounces holds a dozen messages.
The marked success Of the British
pneumatic service led to the adoption
of similar systems in Paris, Vienn, and
Berlin. The pneumatic system of Paris
was put into operation in 1866, and has
grown steadily, so that today in Paris
tubes are used almost exclusively for
transmission of local kilograms and let
ters demanding quick delivery. A small
stamped envelope, the petit bleu, cost
ing so centimes, or 10 cents, is used for
the message, which, dropped into a spe-
cial post-boX, is delivered anywhere
in Paris within an hour, often in % min
utes.
In Vienna the ''tube-pOst" was estab-
lished in March, 1875. The nine dis
tlicts Of the city are connected with q
central station The ''tube-maiP' is
dropped into special post boxes, collect
every half hour, forwarded to the CEN
tral station, and distributed. Pneumat-
ic envelopes cost Is kreuZers about 6
cents, ordinary letters 3 kreuzers.
Tube letters are delivered within one
hour after mailing. The Vienna sys-
tenn consists of a main circuit of 5.34
miles, with three branch lines; total
length - miles.
In Berlin the Prllssian postal authori-
ties began in 1862 discussion of meas
ures OF relief for the overcrowded local
telegraph System, hnd a pneumatic
line was opened in 1865 between the
Central Telegraph station and the EX-
change building. The beginning of the
present extensive tube post of Berlin
dates from 1876, since which time it.
has been enlarged, until there are now
over % miles of trlbe-line in the city,
with SO stations. '"Tube-letters' are to-
day delivered in Berlin more quickly
than kilograms at a cost equivalent to
Z IL cents, and tube postcards at
6 Il cents. The tubes in Berlin are Of
wrought iron, and have an inner diane
ter of 60 NM, ee1ual to 2.55 inches.
The system is operated by eight steam
engines, aggTegating only 1913 horse
power.
The British tube-lines are Laid on the
radial system; that is, the different lines
radlate from centerS to the various
branch stations to be reached In
Paris, Vienna, aid originally in Berlin,
the various stations We're connected by
o series of pOlygOns, around which the
motion is uniformly in the same direc-
ton. A study Of the two systems. for
connection of a given number of sta
tons under ordinary conditions, leads
to the following comparative results:
I. The polygonal system will require
about 20 per cent. more tube-length
than the radial.
II. The polygonal system allows
much greater use of compressed air for
forwarding, as the passage around the
pOlygOns is always in the same direc-
ton. Rarefied air need be used only
for the return passage in the links con-
from a single, isolated station. In the
radial system, Tarefied air is used for
half the passages. This shows greater
economy in working for the polygonal
system.
III. The time consumed in commune
eating between stations is less in the RI
dial than in the pOlygnal system. In
the latter, time is frequently lost by
sending a message almost completely
around the polygon.