IMPROVEMENTS IN THE TRANSPORTATION OF LETTERS, PARCELS, AND OTHER FREIGHT BY ATMOSPHERIC PRESSURE AND IN APPARATUS CONNECTED THEREWITH
Year: 1869

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane,
in the County of Middlesex, Patent Agent, for the Invention
of "IMPROVEMENTS IN THE TRANSPORTATION OF LETTERS, PARCELS, AND
OTHER FREIGHT BY ATMOSPHERIC PRESSURE AND IN APPARATUS CONNECTED
THEREWITH."-A communication from abroad by Alfred Ely Beach,
of Stratford, Fairfield County, State of Connecticut, United States of
America.
PROVISIONAL SPECIFICATION left by the said Alexander Melville.
Clark at the Office of the Commissioners of Patents, with his
Petition, on the 9th November 1869.
I, ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN THE TRANSPORTATION OF LETTERS, PARCELS,

page_text: AND OTHER FREIGHT BY ATMOSPHERIC PRESSURE AND IN APPARATUS CONNECTED
THEREWITH," to be as follows:-
The usual atmospheric method of transporting freight is by means of
vehicles such as cars, balls, bags, or hollow pistons which contain the
freight and fit within a tube and are therein propelled by the force of an
air current.
The object of the present improvements is to dispense with the use of
such vehicles and transport the freight by submitting it to the direct
action of the air currents.
This Invention further consists in the employment of certain devices
to facilitate the receiving and discharging of the freight as herein-after
set forth.
Figure 1 of the accompanying Drawings is a perspective view showing
the employment of a part of the improvements in connection with a
street lamp post letter box; Figure 2 is a sectional end elevation of one
of the improved receiving and discharging letter boxes; Figure 3 is a
sectional side clevation of the same; Figure 4 is a side elevation of a
modified form of receiving box; Figure 5 is a plan view in part section
of the improved shifting air pipe. Similar letters of reference indicate
corresponding parts in the several Figures.
In carrying out this Invention I provide air tubes A, A', A", made of
wood, metal, or other materials of suitable size and strength having a
smooth interior. In some cases the interiors of the tubes are lined with
cloth or rubber or other soft material. By means of a suitable blowing
engine I drive or draw a current of air through the tubes A, A', A", of
sufficient force to buoy and carry along all letters, parcels, or other
freight that may be deposited within the tubes at any point on the
route thereof. In order to discharge from a deposit the parcels
or other freight within the tubes I combine therewith at suitable
places the rotary boxes C. These boxes are composed of wings or
partitions a, a, a, a, mounted on and radiating from a central shaft b,
forming compartments 1, 2, 3, 4, for the reception of letters and parcels.
The outer edges of the wings a are intended to move in contact with the
casing B, the arrangement and construction of the wings and casing
being such that in whatever position the may happen to stand two
or more of them will always be in contact with the casing B, and
thereby prevent the escape of air to or from the pipes A. Letters,
parcels, and freight intended for the air tubes A, arc placed within

page_text: the mouth or hopper B', whence they fall into the uppermost com-
partment of the rotary letter box C, the crank c is then turned and the
contents of the compartments fall into the air tubes A, and are at once
carried along in the tubes by the air current, the course of which is
indicated by the arrows. The letter box C may be employed in the
several offices and stations of the pneumatic route as in Figures 2
and 3, and may be also arranged within suitable pedestals or street
lamp posts as indicated in Figure 1..
I
Various modifications may be made of the letter receiving and dis-
charging devices all capable of effecting the same necessary result, namely,
the deposit and discharge of freight into and from the air tubes without
escape or access of air. One example of such modifications is shown in
Figure 4 in which K is a pipe communicating with the air tube A.
The upper part of the pipe K is closed with a cover through which is
a slot for the introduction of letters. Slot g is covered to prevent
escape of air from tube A by means of the cover L which is hinged at h
to the cover f. An ear i projects from cover L, and a spring rod M
extends from car i and connects the one end of valve N which is so
pivoted and arranged within the pipe K that when the cover L is closed
the valve N. will stand open; but when the cover L is raised for tho
insertion of letters the valve N will cut off the escape of air through
slot by closing against the bottom of the sleeve O which surrounds
slot 9, and is fastened to the under side of cover f. When the cover L
is again closed the valve N will open and the deposited letters will fall
into the air tube A. The above modification may be readily arranged
within the street lamp posts. At the stations where the letters, parcels,
and other articles are to be discharged from the air tubes A, the latter
are separated, and the separated ends are enclosed within an air-tight
box D, the lower portion of which is narrowed down as in Figures 2
and 3 until it forms a suitable casing for one or more of the rotary
receiving boxes C. before described. The interior of the box D, is divided
vertically into two compartments by the wire gauze partition E, the
object of which is to arrest all letters and parcels that issue from the
pipes A, but permit the air current to pass without interruption from
the end of one pipe into the other. The action will be the same no
matter in which direction the air current moves. All letters and parcels
which arrive at the box D will be discharged therein and fall down into
the box C, and on. turning the crank c they will be discharged as shown

page_text: in Figure 3 without interrupting the flow of the air current or permitting
access of air to or from the box D or tubes A.
An
In operating the improvement for postal purposes, all letters deposited
in the tubes at the various receiving boxes will be discharged at the
first way station where the pipes A are separated, and where one of the
boxes D is located. All letters not intended for that station will
be returned to the tube A by the attendant to be carried onward to
the next station. In some cases it is desirable to have one or more of
the tube ends at way stations made movable, so as to open and discharge
their contents at such stations or remain closed so as not to discharge
or move, so as to communicate with a diverging route of tubes.
arrangement for this purpose is shown in Figure 5. One end of the
tube A¹ is made movable so that it may be jointed to or unjointed
from the fixed end A or brought into communication with the diverging
line of tubes A. The joint between A' and A. is covered with an elastic.
band d to prevent escape of air. When the pipe A' is moved aside out
of line with A, into the position shown by the dotted lines, the contents
of the tubes will be discharged at y. When the joint A' is further
moved it will form a junction with the branch or diverging line of
tubes A. The joint tube A' may be operated by the hand of an
attendant, but the presence of an attendant is not essential, as the
tube A' may be readily operated by means of an electric wire extending
from a central station. An electric apparatus for this purpose is
shown in Figure 5, the ratchet wheel F is operated by the armature
pawl G of the electro-magnet H. The link I connects the wheel F
with the shifting tube A', and by the rotation of the wheel F, the position
of the tube A' is changed as desired. When the operator at. a central
station wishes to change the position of the movable tube A' at a way
station he operates an ordinary finger key or circuit closer which is
connected with an electric battery and with the electro-magnet H.
The electric impulse is thus made to pass through the magnet H, which
draws the armature pawl G into connection with the poles of the magnet
and the ratchet tooth m on the pawl G engages the teeth of the wheel F
causing it to rotate in the direction of the arrow. J is another circuit
closer for signalizing back to the operator at the central station. The
circuit closer J engages at one end with pins e on the wheel F, and at
the other end with the wire J' which extends to the central station.
When the wheel F has been so turned as to draw aside the tube A' into

page_text: the dotted position the contents of the tubes will be discharged, and one
of the pins e will lift J, causing its near end to touch the wire J', and
transport a signal to the central office, which signal may consist of a
stroke upon a bell. The pins e are so arranged upon the wheel F in
connection with the circuit closer J that each complete change of
position of tube A' made by the operator at the central station will be
signalized back to the operator. The proper methods of arranging the
electrical apparatus to accomplish the turning of the wheel F and the
return signalizing will be readily understood by the skilled mechanic
without further description. The movable tube A' and its necessary
adjuncts are intended to be arranged to operate in connection with the.
boxes D before described so that the air tube may be opened and closed
and the delivery of freight may be made at any way station either by an
attendant or by the operator at a central station.
I do not limit or confine myself to the particular form or construction
of any of the parts herein described as they may be varied in many ways
without departing from the Invention.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alexander Melville Clark in the Great Scal Patent
Office on the 6th May 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
MELVILLE CLARK, of 53, Chancery Lanc, in the County of Middlesex,
Patent Agent, send greeting.
.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Ninth day of November, in the year
of our Lord One thousand eight hundred and sixty-nine, in the thirty-
third year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Alexander Melville Clark, Her special
licence that I, the said Alexander Melville Clark, my executors,
administrators, and assigns, or such others as I, the said Alexander
Melville Clark, my executors, administrators, and assigns, should at
any time agree with, and no others, from time to time and at all
times thereafter during the term therein expressed, should and lawfully
might make, use, exercise, and vend, within the United Kingdom of
Great Britain and Ireland, the Channel Islands, and Isle of Man,

page_text: an Invention for "IMPROVEMENTS IN THE TRANSPORTATION OF LETTERS,
PARCELS, AND OTHER FREIGHT DY ATMOSPHERIC PRESSURE AND IN APPARATUS
CONNECTED THERE WITH," a communication to me from abroad by Alfred
Ely Beach, of Stratford, Fairfield County, State of Connecticut, United
States of America, upon the condition (amongst others) that I, the 5
said Alexander Melville Clark, my executors or administrators, by an
instrument in writing under my, or their, or one of their hands and
seals, should particularly describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, and cause
the same to be filed in the Great Seal Patent Office within six calendar 1
months next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said. Alexander Melville Clark, do
hereby declare the nature of the said Invention, and in what manner
the same is to be performed, to be particularly described and ascertained
in and by the following statement, reference being had to the Sheet of 1
Drawings hereunto annexed, and to the letters and figures marked
thereon (that is to say) :-
The usual atmospheric method of transporting freight is by means
of vehicles, such as carriages, balls, bags, or hollow pistons, which
contain the freight and fit within a tube, and are therein propelled by 2
the force of an air current.
The object of the present improvements is to dispense with the use of
such vehicles and transport the freight by submitting it to the direct
action of the air currents.
This Invention further consists in the employment of certain devices
to facilitate the receiving and discharging of the freight, as herein-after
set forth.
DESCRIPTION OF DRAWINGS.
Figure 1 is a perspective view showing the employment of a part of
the improvements in connection with a street lamp post letter box;
Figure 2 is a sectional end elevation of one of the improved receiving
and discharging boxes; Figure 3 is a sectional side elevation of the
same; Figure 4 is a side elevation of a modified form of a receiving box;
Figure 5 is a plan view, in part sectional, of the improved shifting air
pipe of this Invention. Similar letters of reference indicate corresponding
parts.

page_text: The outer
In carrying out this Invention I provide air tubes A, A', A", made of
wood, metal, or other materials of suitable size and strength, having a
smooth interior. In some cases the interiors of the tubes are lined with
cloth or rubber or other soft material. By means of a suitable blowing
engine I drive or draw a current of air through the tubes A, A', A", of
sufficient force to buoy and carry along all letters, parcels, or other
freight that may be deposited within the tubes at any point on the
route thereof. In order to discharge from a deposit the letters, parcels,
or other freight within the tubes I combine therewith at suitable places
the rotary boxes C. These boxes are composed of wings or partitions a,
a, a, a, mounted on and radiating from a central shaft b, forming com-
partments 1, 2, 3, 4, for the reception of letters and parcels.
edges of the wings a are intended to move in contact with the casing B,
thic arrangement and construction of the wings and casing being such
that in whatever position the wings may happen to stand, two or more
of them will always be in contact with the casing B, and thereby
prevent the escape of air to or from the pipes A. Letters, parcels, and
freight intended for the air tubes A are placed within the mouth or
hopper B', whence they fall into the uppermost compartment of the
rotary letter box C; the crank c is then turned and the contents of the
compartments fall into the air tubes A, and are at once carried along
in the tubes by the air current, the course of which is indicated by the
arrows. The letter box C may be employed in the several offices and
stations of the pneumatic route, as in Figures 2 and 3; and may be
also arranged within suitable pedestals or street lamp posts, as indicated
in Figure 1.
Various modifications may be made of the letter receiving and dis-
charging devices, all capable of effecting the same necessary result,
namely, the deposit and discharge of freight into and from the air tubes
without escape' or access of air: One example of such modifications
is shown in Figure 4, in which K is a pipe communicating with the air
tube A. The upper part of the pipe K is closed with a cover f, through
which is a slot g for the introduction of letters. The slot g is covered
to prevent escape of air from tube A by means of the cover L, which is
hinged at h to the cover f. An ear i projects from cover L, and a spring
rod M extends from cari and connects with one end of valve N which
is so pivoted and arranged within the pipe K that when the cover L is
closed the valve N will stand open, but when the cover L is raised for

page_text: the insertion of letters the valve N will cut off the escape of air through
slot g, by closing against the bottom of the sleeve O, which surrounds
slot and is fastened to the under side of cover f. When the cover L
is again closed the valve N will open and the deposited letters will fall
into the air tube A. The above modification may be readily arranged
within the street lamp posts. At the stations where the letters, parcels,
and other articles are to be discharged from the air tubes A the latter
are separated, and the separated ends are enclosed within an air-tight
box D, the lower portion of which is narrowed down, as in Figures 2
and 3, until it forms a suitable casing for one or more of the rotary
receiving boxes C before described. The interior of the box D is divided
vertically into two compartments by the wire gauze partition E, the
object of which is to arrest all letters and parcels that issue from the
pipes A, but permit the air current to pass without interruption from
the end of one pipe into the other. The action will be the same no
matter in which direction the air current moves. All letters and
parcels which arrive at box D will be discharged therein and fall down
into the box C, and on turning the crank 6 they will be discharged, as
shown in Figure 3, without interrupting the flow of the air current or
permitting access of air to or from the box D or tubes A.
In operating the present improvements for postal purposes all letters
deposited in the tubes at the various receiving boxes will be discharged
at the first way station where the pipes A are separated and where one
of the boxes D is located. All letters not intended for that station will
be returned to the tube A by the attendant, to be carried onward to the
next station. In some cases it is desirable to have one or more of the
tubo ends at way stations made movable, so as to open and discharge
their contents at such stations or remain closed, so as not to discharge
or move, so as to communicate with a diverging route of tubes. An
arrangement for this purpose is shown in Figure 5. One end of the
tube A is made movable, so that it may be jointed to and unjointed
from the fixed end A, or brought into communication with the diverging
line of tubes A". The joint between A' and A is covered with an elastic
band d to prevent escape of air. When the pipe A' is moved aside out
of line with A, into the position shown by the dotted lines the contents
of the tubes will be discharged at y. When the joint A' is further
moved it will form a junction with the branch or diverging line of
tubes A". The joint tube A' may be operated by the hand of an

page_text: attendant, but the presence of an attendant is not essential, as the
tube A' may be readily operated by means of an electric wire extending
from the central station. An electric apparatus for this purpose is
shown in Figure 5, the ratchet wheel F is operated by the armature
pawl G of the electro-magnet H. The link I connects the wheel F
with the shifting tube A', and by the rotation of wheel F the position
of tube A' is changed as desired. When the operator at a central station
wishes to change the position of the movable tube A' at a way station
hc operates an ordinary finger key or circuit closer, which is connected
with an electric battery and with the electro-magnet H. The electric
impulse is thus made to pass through the magnet H, which draws the
armature pawl G into connection with the poles of the magnet, and the
ratchet tooth m on the pawl G engages the teeth of wheel F, causing it
to rotate in the direction of the arrow. J is another circuit closer for
signalizing back to the operator at the central station. The circuit
closer J engages at one end with pins e on the wheel F, and at the
other end with a wire J' which extends to the central station. When
the wheel F has been so turned as to draw aside the tube A' into the
dotted position the contents of the tubes will be discharged, and one of
the pins e will lift J, causing its near end to touch the wire J' and
transmit a signal to the central office, which signal may consist of a
stroke upon a bell. The pins e are so arranged upon the wheel F in
connection with the circuit closer J that cach complete change of
position of tube A' made by the operator at the central station will be
signalized back to the operator. The proper methods of arranging the
electrical apparatus to accomplish the turning of the wheel F and the
return signalizing will be readily understood by the skilled mechanic
without further description. The movable tube A' and its necessary
adjuncts are intended to be arranged to operate in connection with the
boxes D before described, so that the air tube may be opened and closed
and the delivery of freight may be made at any way station either by
an attendant or by the operator at a central station.
Having described the nature of the Invention, and the manner of
performing the same, I would observe that I do not limit or confine
myself to the particular form or construction of any of the parts herein
described, as they may be varied in many ways without departing from
this Invention; but I declare that what I claim as the Invention to be
protected by the herein-before in part recited Letters Patent is,-

page_text: 1st. The transportation of letters and parcels by submitting the same
to the direct action of air currents within conveying tubes, substantially
as herein set forth.
2ndly. The combination with the air tubes of a mechanism for
depositing the letters or parcels within the air tubes, so operating as to
prevent air escape, substantially as set forth.
3rdly. The combination with the air tubes of a mechanism which will
collect or arrest the contents of the tubes without interrupting the flow
of the air current, substantially as set forth.
4thly. The combination with the air tubes of a discharging mechanism
so operating as to prevent air escape, substantially as set forth.
5thly. Operating the movable portions of the air tube by electricity,
substantially as and for the purpose set forth.
6thly. Effecting the return signals, substantially as set forth.
In witness whereof, I, the said Alexander Melville Clark, have
hereunto set my hand and seal, this Sixth day of May, in the year
of our Lord One thousand eight hundred and seventy.
Witness,
W. CLARK,
53, Chancery Lane.
A. M. CLARK. (L.S.)