A CRYPTOGRAPHIC MACHINE OR APPARATUS FOR CARRYING ON SECRET CORRE- SPONDENCE
Year: 1859

page_text: LETTERS PATENT to Richard Archibald Brooman, of 166, Fleet Street,
in the City of London, E.C., Patent Agent, for the Invention of "A
CRYPTOGRAPHIC MACHINE OR APPARATUS FOR CARRYING ON SECRET CORRE-
SPONDENCE."-A communication from abroad by Jules François Victor
Mouilleron, of Paris.
Sealed the 11th April 1860, and dated the 20th October 1859.
PROVISIONAL SPECIFICATION left by the said Richard Archibald
Brooman at the Office of the Commissioners of Patents, with his
Petition, on the 20th October 1859.
I, RICHARD ARCHIBALD BROOMAN, of 166, Fleet Street, in the City of
London, E.C., Patent Agent, do hereby declare the nature of the said
Invention for "A CRYPTOGRAPHIC MACHINE OR APPARATUS FOR CARRYING ON
SECRET CORRESPONDENCE," (communicated to me from abroad by Jules François
Victor Mouilleron, of Paris,) to be as follows:-
The object of this Invention is to provide a machine or apparatus by means
of which secret correspondence for diplomatic and other purposes may be

page_text: carried on conveniently, and so as effectually to prevent the deciphering of the
despatches by any person not in possession of the key to the same.
The main feature of the Invention consists in the employment of several
pairs of alphabets, one alphabet of each pair being capable of longitudinal
motion along the other, so as to bring different letters of the two alphabets
opposite each other. By arranging the several pairs of alphabets according
to positions indicated by means of a "key word," and a standard pair of
alphabets, and transmitting in succession the letters found on one of the two
alphabets opposite to the proper letters of the despatch on the other, the
several pairs of alphabets being successively used, a despatch in cipher may be
sent, which despatch may be readily interpreted by reading the letters of one
of the sets of alphabets found opposite to the received letters on the other set,
or in other words by reversing the sending process.
In the machine or apparatus devised by the Inventor for these purposes,
the movable alphabets are printed or written on endless bands or tapes which
pass round rollers and may be driven by pinions or otherwise. All the pairs
of alphabets are mounted on an axle, which is caused to rotate by a crank
handle or otherwise, so as to bring successive pairs of alphabets into view.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Richard Archibald Brooman in the Great Seal Patent Office
on the 20th April 1860.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, RICHARD
ARCHIBALD BROOMAN, of 166, Fleet Street, in the City of London, E.C.,
Patent Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twentieth day of October, in the year of our Lord One
thousand eight hundred and fifty-nine, in the twenty-third year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Richard Archibald Brooman, Her special licence that I, the said Richard
Archibald Brooman, my executors, administrators, and assigns, or such others
as I, the said Richard Archibald Brooman, 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

page_text: Britain and Ireland, the Channel Islands, and Isle of Man, an Invention
for "A CRYPTOGRAPHIC MACHINE OR APPARATUS FOR CARRYING ON SECRET CORRE-
SPONDENCE," (communicated to me from abroad by Jules François Victor
Mouilleron, of Paris, upon the condition (amongst others) that I, the said.
Richard Archibald Brooman, my executors or administrators, by an instru-
ment 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 months next and immediately.
after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Richard Archibald Brooman, 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 thereof, reference being had to the Drawings hereunto- annexed/
that is to say:-
The object of this Invention is to provide a machine or apparatus by means.
of which secret correspondence for diplomatic and other purposes may be
carried on conveniently, and so as effectually to prevent the deciphering of
the despatches by any person not in possession of the key to the same.
The main feature of the Invention consists in the employment of several
pairs of alphabets, one alphabet of each pair being capable of longitudinal
motion along the other, so as to bring different letters of the two alphabets
opposite each other. By arranging the several pairs of alphabets according.
to positions indicated by means of a "key word;" and a standard pair of
alphabets, and transmitting in succession the letters found on one of the two
alphabets opposite to the proper letters of the despatch on the other, the
several pairs of alphabets being successively used, a despatch in cipher may
be sent, which despatch may be readily interpreted by reading the letters of
one of the sets of alphabets found opposite to the received letters on the other
set, or in other words by reversing the sending process.
In the machine or apparatus devised by the Inventor for these purposes;
the movable alphabets are printed or written on endless bands or tapes, which
pass round rollers by pinions or otherwise. All the pairs of alphabets are
mounted on an axle, which is caused to rotate by a crank handle or otherwise,
so as to bring successive pairs of alphabets into view.
Figure 1 of the accompanying Drawings is a front view, and Figure 2 a
side view of a box containing an apparatus constructed according to this
Invention. is the box, which is made by preference in the form of a desk,

page_text: but it may be made in any other form. The two Figures just mentioned are
drawn on a very reduced scale, but the general mechanism of the machine is
shown on a large scale in horizontal section at Figure 3, in transverse section
at Figure 4, and in detail at Figure 5: The machine contains by preference
five double alphabets a, a', arranged round two cross-bars c, c¹, carrying five
face plates, the latter plates being in number equal to the number of alphabets
employed. The number five is chosen on account of its being at present used
in telegraphic and diplomatic correspondence, and being known to present
less decipherable combinations than any other, but any other number can if
desired be employed. The upper alphabet a is fixed in such manner that it
can neither move to the right nor to the left; the other and lower alphabet a
is free to move at will from right to left, or vice versa, in order to cause the
letters of the moveable alphabet a¹ to correspond according to the key "word "
with the letters of the fixed alphabet a. The cross bars c, c³, are placed on
the same axle, to which an intermittent rotary motion is imparted by means
of a crank or button b in the following manner. On the left hand side of the
desk k, Figures 1 and 3, a button 6 is placed, which is free to slide in a
groove, on motion being communicated to it by the hand. This button is
attached to a rod f, against which a spring 9 (shown on a larger scale at
Figure 6) acts and imparts to it a backward motion in order to draw the button
to the groove e, when the hand is released from the said button by the traction
of the rod f, the lever h forces the guard of an arm j to turn one division of
a star wheel m. This star wheel is fixed on the shaft d of the cross bars c, c',
and is acted on by a cam n, in one division of which the rollers o, o', engage.
Thus, by means of this mechanism, the traction of the button 6 in the groove e,
makes the axle d of the cross bars turn one division, that is to say, supposing
the five alphabets to be numbered 1, 2, 3, 4, and 5, at each draw of the
button 6 a successive change in the alphabet would be produced. Independent
of this intermittent rotary motion to produce the changing of the alphabets
the lower alphabet a' on each face receives a rectilinear longitudinal motion
while the upper alphabet remains fixed. The lower alphabet is printed on an
endless band, which passes round and is supported during its course by small
rollers 1,. The motion of the band is produced by the arrangement of
mechanism, shown at Figure 5. The rod 9 of a button p (Figures 1 and 5)
is prolonged through the box k to the end of the right of the alphabets; it is
there held by a lever r, which brings back by its upper forks the felt or india-
rubber disc t against one of the rollers of the band a¹. By pressing a finger
on the button p at the time the contact of the disc with the roller / takes

page_text: place, the crank u, Figures 1, 3, and 5, turns, the motion being produced by.
the frictional contact at the disc t with the roller l, and consequently the
band a participates in the motion. On removing the finger from the button p
the lever r being drawn back by the spring v, Figure 5, removes the disc t
from the roller l. A pentagon or five-sided Figure x carrying the numbers
1, 2, 3, 4, and 5, which are the indicator of the numbers of the five
alphabets is placed right and left of the axis d.
The operation of the apparatus is as follows:-
First. The composition of the key.-Take, for example, any word composed
of ten letters, for instance, the word "recusation," the word is divided into:
two parts, each part composed of five letters, that is, "recus" and "ation;"
the characters 1, 2, 3, 4, and 5, which represent the five faces of the
pentagon c, c', are written on a sheet of paper which is placed below the five
letters r. e. c. u. s. and below these the other five letters a. t. i. o. n. The five
letters r. e. c. u. s. are taken on the five faces of the upper alphabet a; the
five letters a. t. i. o. n. are taken each respectively on the lower alphabet a¹ by
shifting them along the preceding letters. To produce this effect, draw out
the button b, which turns the pentagon c, c, in such manner that the face
No. 1 of the alphabet comes in sight; then press the left hand on the button p,-
and turn the crank u with the right hand; the band a¹ slides along until the
first letter a. of "ation" comes below the first letter r. of "recus." Again
draw the button 6 in order to present to view the face No. 2 of the alphabet;
then slide the band a¹ of this alphabet No. 2 until the second letter t. of
"ation" arrives in the alphabet a below the second letter e. of "recus," and so
on for the five faces of the pentagon. The key-word being thus arranged
correspondence can take place.
Second. For a dispatch or message.--For instance, if the words "good success"
are to be forwarded, the sender takes the instrument and causes the face No. 1
of the pentagon to present itself; he then ascertains what is the letter on the
lower and movable alphabet which corresponds to "g." on the fixed alphabet,
and he writes this letter on the paper; he then turns the pentagon to bring.
forward the face No. 2, and ascertains what is the letter on the movable
alphabet corresponding to the letter o. on the upper alphabet, and he writes.
this new letter, and so on. Thus the dispatch of the sender is composed by
reading on the fixed alphabet, and by writing the corresponding letter taken
on the movable alphabet.
Third. For the reading of a dispatch or message.-The person who receives
the dispatch places the pentagon on the face No. 1, and reads on the movable

page_text: alphabet; he then writes the letter which on the fixed alphabet corresponds
with the letter on the movable alphabet, that is, he does the contrary to that
which the sender did.
Such is the description of the cryptographic machine represented at Figures
1, 2, 3, 4, 5, and 6 of the Drawings. Figures 7 and 8 represent, under a
more simple form, a pocket or office instrument constructed in a similar
manner, being more suitable for business, commerce, and private corre-
spondence, than the apparatus before described. On the tablet 6%, which is
formed of wood, cardboard, metal, or any other suitable material, a fixed
alphabet a is arranged; a second alphabet a', which is reversed and movable, is
placed below the first; the second alphabet a¹ consists of an endless band of
metal, leather, or other material, upon which the letters are written. This
endless band is wound round two rollers or cylinders 1, 7, at each end of the
tablet 6, the said rollers being free to turn about the axis d¹. A small band
forming the movable alphabet works by means of a slide or button e¹³, Figure 8,
in such manner as to produce the motion of the said alphabet each time it is
required to change the letter in relation to the key word. g, g', are leaves or
covers which can be raised when required. The movable alphabet a¹ can
moreover be placed on a guide gauge sliding in longitudinal grooves of the
tablet 1, but in this case a to-and-fro motion is given to the endless band.
The guide is twice the length and carries two alphabets.
Figure 9 is a view of another cryptographic machine suitable for the pocket,
being a modification of the one just described. This one is composed of a
fixed alphabet a and of five movable alphabets a², each one being independent
of the other, and arranged in relation to the characters 1 to 5, which corre-
spond to the five letters of the key word. The arrangement of this apparatus
is very simple; on a frame 62, of wood, pasteboard, or sheet metal, the fixed
alphabet a is arranged. Each movable alphabet a¹ placed with relation to the
characters 1 to 5 is arranged on an endless band, entering by each of its ends
into the slits f¹ of the side pieces, where they are rolled round small rollers, as
shown at Figures 4 and 5. Each endless band a¹ carries on the other face
of the frame 6 a small button, tassel, or ribband intended to assist in moving
the alphabets.
The Inventor does not limit himself to the precise arrangements before
described, nor to the precise forms of apparatuses shown, nor to the exact
number of alphabets employed, as the same can be varied without departing
from the essential features of the Invention.
And having now described the nature of the said Invention, and in what

page_text: manner the same is to be performed, I declare that I claim as the crypto-
graphic machine or apparatus for carrying on secret correspondence,―-
First, the machine herein-before described and illustrated at Figures 1, 2,
3, 4, 5, and 6 of the accompanying Drawings.
Second, the portable apparatus as described and illustrated at Figures 7 and
8 of the accompanying Drawings.
And, third, the machine more particularly designed for carrying in the
pocket, as herein-before described and illustrated at Figure 9 of the accom-
panying Drawings.
In witness whereof, I, the said Richard Archibald Brooman, have here-
unto set my hand and seal, this Twentieth day of April, One thousand
eight hundred and sixty.