The Utah County Democrat. [volume] (Provo City, Utah) 1898-1909, 1899-04-01
prOvo Il. c. N. L.
L. o. Taft, Manager.
Pneumatic Mail Delivery.
SALT LAKE. March 81, 1899.

SALT LAKE. March ~, 1899.
Editor DEMooRAT-B Believing that
asscrlniion of the New York pneumatic
mail delivery will be of interest TO
some of your readers proceed to give
!, IT, has already been recorded In
some. or. in fact, all tie leading scien-
,iac pub ications. The system Is now
mod over considerable portion OF the |
old city, and is being placed through The
great city. with all its adjoining cities,
which is all New York, connecting
them with the general office.
This system OF pneumatic tubes is
the invention OF the chief engineer OF
the Balcheller Pneumatic Tube com
psny. The tube consists of casllron
pipes In twelve foot lengl his and eight
and one-eik hih inches internal diane
ter, being bored smooth, aud the IONS
being made with great care to .xaci
alignment. They are laid side by side
under the city street. taking the most
direct line that could be found between
the different stations. After being
bored GU smooth these pipes are lett
nye eigh, his of an inch thick. All bends
are made by means OF brass tubing "i
eight and three-righths inches internal
diameter, the greater size being To pre-
vent tanning ~ the curriers' Thes"
pipes are bent To not less than eight
feet radius. Short lengths OF iron pipes
with a conlcll bore are useh at IN
Joints with the brass tubes, To gradual
" Increase or reduce the bore.
Tue carriers are cy iindrical, being two
feet long and seven incnrs IA internal
diameter. aud have II capacity OF rom
900 TO $40 letters. The carriers are made
OF sheet steel one-thrly second of an
inch thick aud open ut Que end. iht
cover for this opening being fitted WIN
a device which locNs 1t only when th'
carrier is In The tube. Each carrier u
fitted with two bearing rings oi
nbrous material, Que paced near eacf
end; making the carrier resein"ie
spool af err the thread Is taken on. IN
ring ends being the bearings makes
possible for the carrier Ia lraver''
curves. These rings are the only part
Of the carrier which touches The insld'
OF the tube. and they reduce tue fric
ton 10 the minimum. The rings las
for about 1000 miles OF travel In
carriers are propelled through IN
tubes by continuous current Oh AL
generated by Raud Duplex air con
pressor, placed in the baseInenL ~ u
general postoflice. This air curreI
passes through Que tube 10 the sub-sti
ton. aud returns through The oih'
tube IN tank In the engine ro"i
from which tank In turn, the AIR
again Iaken up by the compressor'lh '
forming complet circuit. The col
pressor, whose cylinders are INVENT
four inches In diameter by twen
inch stroke. were built by the kai
Drill comp my. from specifications
the Ba,cheAer Pneumatic Tube Col
pany. They can deliver the ar
eleven pounds pressure, although
pounds is all that Is now being u.s.
The speed of air current, ana coh'
QueutIy OF the carriers, is about ~
ieet per minute.
The transmitting and receiving III
chlnery in the general pOst"tiice
placed on the main door OF the bull
ing. Al the end of the iransmll'l
lube is cradle. by means of winch !
carrier Is thrown into position. SINH
to a repeating rife. When no carr
Is being sent the air current from I
delivery pipe passes directly lnto
lube through one arm OF the Grad
which resembles the cylinder OF II
vover, hut when the cradle IS la
act Ut being thrown 10 place the carr
IMPOSITION. the CURRENTS anlolnatica
switched off and goes through
pass, being returned against the r
end OF the carrier as soon as II Is III
slllon. thus starting IL on It's ~
ney through the tube. lnimedi'
y Tier The carrier hns left the crae
the eTa'llr is Automatically returned
its original position. The machine