, 1874-04-25

* * eect1zca4fy With the operating room, Bouns
IS tue information that tbs carrier had arrived
4 1te destination, and the gender OF the mess.
: Instantly cut eff the air-current. Then tho &C
|. stopped sounding, by which it WAS learned II
:. I tie message had been duly received by the T
stairs Attendant, and removed from tia tnl
Ihe reporter examined
which was found to obs bnn ma9a ThE s|un,, =, a++
.. zinc carefully shaped, with the seams an smoo
as possible, and perfectly air-tight After soei,
two or three carriers" sent up, tue report
moved upstairs, where he was shown
THE WESTINGHOUSE INJECTOR
n operation; This apparatus is somewhat aim
ployed on the English lines, though more sir
pie, and the vacuum which creates the draft {
outalde ait ia caused By the rush Of the ordinar
condensed air Of tho tube. It il calculated thu
stneIo injector increases the force Of the 4
current between 50 and 50 per cent.
The next part OF the system to be iugpecte
| Ta8
| n THE opEnATtSo-nooM
OF the Company, where tho reception Of th
messages Was observed. The start OF = car
Ter was announced by a sounding on gon,
similar to that below by the sender. AM
in, moment tho carrier shot out OF th
tube, striking IN its passage cut the Bounder o1
the gong below, which made the sender nc
1uainted with the reception OF the message
The receiver then took the carrier in hand, re-
sounding, thus acQuainting the sender with tho
fact TINT tho carrier had bean received In q
corner OF the operating-room was found one end
OF tue tube connecting tho ". .. r. Co.'s gen
oral opera.inc-room with their Office IN tue
Chamber Of Commerce This line, Col. Wilson
had no loss than six risht-anglel
curves in 1t. The great iacrease OF speo1
attained by the American syytem il
clearly shown in tho working OF this tube
y referring. to tho statement OF time made on
the English lines it will be seen that the fastest
852 yards OF tubing, with both pressure and
Vacuum working. ln one minute and thirteen
seconds, which is at the rate Of about eleven
yards aud two 1oct in a second. As
AN AaRREABLE CONTRAST
to this elow-going result achieved with the ex
pensive and complicated English srstona. il il
pleasing to record the fact that, with pressure
OF only 10 EoundB, 3 message has boep sent
through the Chicago 300-foot tube in three Soc
onds, the ratio Of speed thus boing 50 yards a
second, or more than
THREE TBlEs As FAST
as the English record. When the tanks canab'o
Of supplying q 200 pounds pressure arc in use.
Inc timing OF the carriers run to the " n n
COS operatng-room to the Board OF Trade viii
doubtless, be done with stop-watch. As m;rht
% expected, the sudden stoppago OF the carrier
Without damage at tho mouth Of the tube, when
moving Ut ouch rate Of speed, is matter Of
considerable difficulty. The force with which
:arr!or sent from tho Board of Trade to the ".
J. 1. Co.'S oTerat1ng-Toom leaves the tube il |
ho"n By the fact that, it left unrestraincd, It |
measures about 40 feet, and strikes the wall oDpo-
lte with considerable force. To countarsct this !
title drawback Col. Wilson hns nearly perfected !
u apparatus By which tho messages to and from
he Board of Trade can be received without
anage to the carriers or the messages they con-
1n41Q ur$A NV .1.I |
ach end Of the tube, into which tho carrier will
Q thrown. The side Of the chamber vhicl, will
ecel'e tho full force of tho first blow will be 40
ranged with springs ulAt a perfect dcadeuiusy
the too lively carrier will DO effected, and It
Ill fau back upon tho foot OF the cban,l,ar
hen the escape valve will be lung opco. and
10 carrier, iu1pcllcd By tho mir current. viii be-
und nc@t to tho escape vnlye its exit heino |
ndcred bT movable sieye.
The construction OF
THE BOARD or TRADE TUpH
the same as that a1ready described. bsino or ,
ect zinc one-eighth Of an inch in thicsnees
d three inches in dinmetcr. Tho only protec- }
n 1t has In going under the street whero it il .
d at dcptl, Of throo feet to insure protection !
'm frost OF dampness is its encasement in or :
nary glazed ee~or-pipes. As the constructors :
tho Chicago pneumatic tubes do not bel;eya in ! :
rking with vacuum alone, a tank of tho full | /
Q Is to- be placed in the Chamber of Com !,
rce, which will be fed from the Westinc,,ouso -
pump already spoken Of. One object Of hav- y
q EuthclencY OF tanks is tho sccur- 6
tull supply of compressed ai- with
ich to perform the oreuing's work 1t is cal
ated that one OF the now tanks filed with !
npresscd air will suffice to rim SATURDAY. u y.
nt, all Sunday, and up to Monday morning. :. =
I'M engine out OF gear Tor day or two, there u
lla be no necessity to star work on the tubes ~
: as well before closing the article on pneu- W
.io tubes to mention tho w
MAIN POINTS OF DIFFERENCE ~
Teen the English and American systems. It r.
boen shown that tho carriers sent tl,rourh | ~ :,
American tubes travel somewhat uore tim III
% times rs fast as the fastest motion 1nado r.
he English carriers, and it ia safe to assume 1Nl N
tho average speed attained by the Chicago a. a.
en- will be at least slx times greater than ~: IT,
average speed Of the English t,,bcs. We
he conductors in tho English systen ara Sc
e OF lead drawn into tubes from 11S to 2l6 4il
ca IN diameter, and these. cpcascd in c,S5 Le
socket pipes. arc laid under the street at a ass ass
Il of twelve inches. 4es
TIE CONDUCTORS l.ia
se American system arc of leaYv aheet rim | et5'
1t one-eighth Of an inch in thickness for,ueJ ca
pipes three inches in diameter and fhcao | -
:ncased in the ordinary glazed sewer nines ma ma
lald under ground ut depth Of three feet uoi .a
. e. ahes afe a. BOT affected by frost or ~. s1r
FINISHED by doub]e-acting sir numn m e1s
u oy q large steam engine, Carriers ara ceE
out by thus forcing compressed air into .us, as
), and are brought back again into tho cen. ~
'tatlon by exhausting air from tubes. III III
tho American syAtem the air il furnished hv W.
terry OF three Westinghouse air pumps ,lriyen @ uos
ordinary engine used for heating tbe bn;j5. III
and working the elevator b. tho a..
lb!lng up" System, in connection with thu %, -
giy-buit tanks. tho pressure Of 200 pounds ~, 1
square inch Ii obtained in the tauks wbiie Tus
tenna-boller carries but 40 or 50 pounds Of ~ ~
ure. Tug
,,,,,r,,,, to h
ned by the use of the tanks is tho stor;no y. ~.
supply OF air sufficient to run the t1hes f,9 n ot
Or two without further pumping. an idea rasa rn.'
ists as soon aa ~ ~ the English JUDI
} English use an Intricate steam exha1ster | ~
ate vacuum, while the American INJECTOR "a
II described Is equally eficacious, and as ' 49,
oan .,,hoa ~ ~ !kseH; IN tue bitte
IMPRESSED air, while in the English system H. liz
rrler is returned by an exhausted receiTer IN no
ends OF tho tubes in the English system t:s uekt
roElded with very complicated and e1non ~ s'us ~
alVes, checks, and vacuum chambers for - a. ~ "
ing and dspatchiog car11ers Wills thu 10y 10y
can system provides simply small ar ~ t1oio
chamber, into whic1, the tubes and o;r. LIZ
? pipe lead, together With another small ;. ~
which is to allow the surplus mir ~ u
remains after the reception Of . carrier t.sEi ori