(perforated tape feed of coded picture information, for photoelectric, typewriter etc reproduction)

H. E. Ives patents 1926-1930
US Patent 1,580,896 (1926) "Picture Analysis"

Arthur Korn patents 1902-30
selenium cells, and some indirect method

Bartlane patents 1921-35
H G Bartholomew, M L D McFarlane (and others)
UK Patent 195,577 (1923)
Bartlane : perforated tape patents
Bartlane : image analysis

US Patent No. 1,608,527 (1926)
Facsimile Telegraph System
P M Rainey (assignor to Western Electric)
[ assumes use of a plurality of light-sensitive (selenium) cells, relays, 5-unit code; designed for both synchronous and asynchronous (start-stop) systems; Lucky (dubiously) cites this as first PCM patent; stay tuned ]

UK Patent No. 311,810 (1929)
Picture Transmission System
Bell Telephone Laboratories
[ incorporates photoelectric cells, punched tape, and a page printer device, modified for closer spacing and line feed ; stay tuned ]

UK Patent No. 404,715 (1934)
Improvements in or relating to Picture Transmission Systems
Electrical Research Products (subsidiary of Western Electric)
[ 4x4=16 tones ; stay tuned]

UK Patent No. 257,013 (1926)
Improvements in or relating to the reproduction of pictures, drawings and other representations by the aid of telegraphy
Creed & Co., Ltd.
six diameters of dots, plus (white) space

US Patent No. 1,851,072 (1932)
Apparatus and method for electrical transmission of pictures
Gilbert S Vernam, Edward F Watson and Donald B Perry, assignors to AT&T

scrambled pictures (image ciphering)

UK Patent No. 655,320 (1951)
Facsimile Telegraph Systems
Standard Telephones and Cables, Le Materiel Telephonique


US Patent No. 1,503,590 (1924)
Method and system for transmitting pictures to a distance
Eliot Keen
(representative) acoustic system

introduction (separate page)

elemental types (separate page)

integrated systems

By integrated systems, I mean systems that offer the whole picture-telegraphic package with minimal human intervention : scanning (also called exploration), coding (and possibly counting), production of an intermediate record (e.g., punched tape), transmission, and reconstitution at the receiving end. The systems described above either required the human eye for analysis or were silent on the analysis itself, focussing instead on the elementary signs for reconstitution.

Some of these systems did not involve an intermediate record, but rather synchronous transmission/receiving. Korn and Thorne Baker, for example, preferred these so-called "direct" methods, akin to analog telephony in the kinds of circuits they required.

Moreover, there appears to have been a general movement toward direct methods in which alternating or pulsating signals were transmitted over phone lines. One objective was simplication of the facsimile process, so that "comparatively untrained personnel" could use it. Intermediate perforated tape records did not fit into this objective. And so we have McFarlane and Hansen 1939 US 2,164,038, describing a system that was essentially already in use at that time. In some sense, they were leaving something like PCM coding of pictures -- that is, quanitizing samples -- behind, at about the same time Reeves conceptualized Pulse Code Modulation for telephony.

Direct methods are mentioned mostly in passing below. I focus rather on "indirect" methods involving analysis of pixel-like zones into classes of grayscale values, transmission of that coded information, and reconstitution into "elementary signs" whether they be printed or photographic dots of different sizes, or some other form. The expression "indirect" might also be characterized as a condition of "off line," in which analysis, coding and preparation of perforated tape intermediate records happened separately from transmission.


Herbert E Ives (1882-1953)
picture transmission patents, 1926-1931

1926 US 1,580,896
Picture Analysis
Ives's first facsimile patent contains vestiges of human judgement

1926 US 1,606,227
Transmission of Pictures by Electricity
Joseph W Horton, Herbert E Ives and Maurice B Long
Claims to provide the "working whole" that had not so far become available.

1926 US 1,607,893
Transmission of Pictures by Electricity

1927 US 1,631,963
Transmission of Pictures by Electricity

1928 US 1,683,894
Reproducing Pictures Transmitted Electrically

1928 US 1,688,081
Transmission of Pictures by Electricity

1928 US 1,691,071
Transmission of Pictures by Electricity
Herbert E Ives and Maurice B Long

1929 US 1,717,781
Picture-Transmission System

1931 US 1,815,203
Image Producing System


Buckley, Oliver E. and Karl K. Darrow. 1956. "Herbert Eugene Ives, 1882-1953." National Academy of Sciences, Biographical Memoirs 29 (1956): 144-189 [lists publications, patents; emphasises "scientific" over engineering activities]

Ives, H.E., J. W. Horton, R. D. Parker and A. B. Clark. 1925. "The Transmission of Pictures Over Telephone Lines." Bell System Technical Journal 4 (April 1925): 186-214


US Patent No 1,580,896
application filed : 27 December 1923
13 April 1926

Picture Analysis

Herbert E. Ives (assignor to Western Electric Company


This first of some 15 or so Ives patents for "picture transmission" employs photo-electric cell, plus operator : "An operator by observing the deflections of the indicating instrument may cause the perforation of a tape in accordance with symbols characteristic of the tone value indicated by the indicating instrument. The tape may then be passed through a telegraph transmitter... for causing the operation of a receiving printer which will reproduce the original picture." (1:28ff)

Uses a galvonometer with a graduated scale, but no automatic feed of signal through relays with different settings -- hence need for a human attendant to operate a board of nine "character keys" -- five for tones, one each for carriage return and line feed, plus two keys for completing circuits (2:42ff).

We begin a survey of "automated" systems with this first Ives patent for picture analysis. It is transitional, because an operator must manually key an encoding device -- the tape perforator -- as he or she monitors successive readings from a galvanometer. This vestige of earlier ideas would be gone in Horton Ives and Long 1926/1,606,227, which claimed to be a "working whole suitable for commercial transmission of pictures."

In image below right can be seen an observation microscope "used for inspecting the light valve aperture for adjusting purposes." This device was probably a part of the working prototype machine, and provides yet another vestige of human analysis of the image -- here only to calibrate the galvanometer dial or the relays.

ives_fig7.jpg ives_fig8.jpg

Fig. 7 -- Sending end apparatus showing motor, film carriage, optical system and amplifier modulator.

Ives is at left.

Fig. 8 -- View of receiving end apparatus showing light valve and observation microscope.

ex Ives, Horton, Parker and Clark (1925)

Arthur Korn (1870-1945)
phototelegraphy patents, 1902-1927

1902 UK 1325
A new or improved method and apparatus for the production of phototelegraphic images, pictures or records
employs selenium cells for scanning and reproduction of image

1903 UK 23,876
Improvements in or relating to autographic and other telegraph systems
Cathode tubes for printing at receiving end, either images (one tube) or Morse (two tubes, for "points" (dots) and "dashes", respectively)
see exhibit and explanation below.

1906 UK 16343
new "method of measuring the degree of exposure of a selenium cell"

1907 UK 1548
Improvements in or relating to telautographic systems
Improves on speed at receiving end, by introducing devices for controlling ray of light generated by galvonometer

1907 UK 8727
An improved method of telegraphically transmitting photographs and the like and system therefor
Improved galvanometer, but above all incorporates two selenium cells (one or scanning and one for "compensating the inertia of the first") in the sending instrument alone, rather than placing one in the sending, and one in the receiving instrument. the drawback had been that great distances between stations had worked against maintaining a precise relationship between their respective exposures and drops of potential. (1:22ff)
Printing is done by directing light beam onto sensitive film or paper. see detail at 8:35ff.

1927 US 1,615,015
Telautographic Transmission
Has to do with "automatic production of a typed telegram or of a telegraphic perforated strip from which at the receiving station the picture may be reconstructed." Claims to be an improvement for the (Frederick) Bakewell transmitter (involving tin-foil covered revolving drums for transmitting and receiving recorded pictures); instead of five "feeling pointers," which occasioned some difficulty, one only is used, for "five successive feeling operations being used for the production of a combination of holes or of a letter type." This is effected by means of a non-conducting wheel with embedded conducting elements, which performs the five feeling operations once in each revolution.

1927 US 1,618,964
Uses two photoelectric cells "exposed simultaneously to the variations of irradiation" and a Wheatstone bridge galvanometer, in a device to compensate for inertia of selenium and other photoelectric cells.

1930 US 1,745,018
Picture Telegraph System
devoted to synchronization, by means of "periodic signals of a given frequency which are of a different intensity from those of the superimposed picture signs"


detail of Fig. 2, Korn 1903 GB 23,876

"For producing a telegram for intance in the Morse alphabet preferably two cathodic tubes with narrow windows placed side by side are employed, so that a single stroke produced by the one tube on the sensitive film, paper or the like corresponds to the point in the Morse alphabet and that two strokes simultaneously produced by both tubes correspond to the dash in the Morse alphabet. At the sending station the transmitter is further adapted to produce and transmit at pleasure positive and negative electrical impulses or disturbances. In lieu of the signs of the Morse alphabet some other combinations of signs may be registered in the same manner." (3:11ff)

Where not Morse but "half tone engravings or pictures, manuscripts, sketches and the like" are to be produced, only cathodic tube J1 is used, to expose radiation onto sensitive paper attached to roller K1. When a telegram is to be produced, cathodic tube J1 is disengaged and the two tubes X and Y are engaged. Tube X produces radiation "through its window" for one stroke; tubes X and Y produce radiation to produce two strokes, "which correspond to the dash in the Morse alphabet or to a second sign of another alphabet." (5:16ff)

Korn preferred direct over indirect -- coded, intermediate record -- processes; this is an interesting condundrum in which code itself is treated as a picture.

This specification focuses on the receiving station; at the sending station, "a suitable pencil is employed which touches the surface of the original and is in any well known manner arranged for opening and closing the sending circuit..." (2:45ff)

Korn and the "indirect method"

Thorne Baker (1927) writes :

"A further method of employing a code was adopted recently by Korn, who devised an instrument for rapidly assigning to the unit tones of a photographic image the appropriate code letters, and a second instrument rather on the lines of a typewriter for reconstructing the image from the code telegram. The latter could, of course, be sent equally well by wire or wireless, and an actual example of such a code transmission from the United States to Italy is seen in Fig. 11. The code method has appealed to the imagination of many inventors, but it seems doubtful whether in the long run it can vie with more direct processes." (20)

The same image is presented in Korn's own Bildtelegraphie (1927), in chapter 11 devoted to such "indirect methods". Chapter 11 of that book runs as follows (my rough Englishing, with thanks to Dorothee Weinlich in Berlin) :

I would like further to briefly mention methods by which pictures may be transmitted by cipher telegrams and punched tape. Individual picture elements are photoelectrically scanned and translated into ciphers. For example, a light picture element is assigned the letter "A", a dark element the letter "Z", and the remaining graduated tones are assigned their respective letters, which are then transmitted telegraphically.

One can also use photoelectric cells to generate differerent current strengths for the different brightnesses of each picture element; these in turn can actuate the different letters of a printer for the automatic dispatch of a telegram. The telegram is sent in the usual way, by cable or wireless, and the picture is reconstituted at the receiving end. The same can happen with the use of punched tape; the recomposition of the image is done with a simple typewriter, where the typebars bear not individual letters but small squares or rectangles whose dimensions range from large to small, each representing the tone assigned to its letter. For a "Z", a small rectangle is printed that fills out a grid space. A "Y" will be a somewhat smaller rectangle, and so on down down to the smallest point. The "A" bar will leave an empty space. Thus does one print one picture element after another, following the received telegram, to build up the same picture that was originally scanned and transformed into a cipher telegram.

In this way, I effected a wireless transmission of a photograph over the ocean, from Rome via Nauen and Bar Harbor to New York, in 1922.

I prepared a similar method also for black and white, obtaining the advantage that a single letter can represent five successive picture elements, and so reduce telegram wordcount down to one fifth.

These indirect methods offer obvious advantages over direct methods: (a) scanning and reproduction at the receiver end are done off-line, and do not tie up long-distance circuits or wireless stations, and (b) they require only the usual telegraph working. There are no requirements for synchrony between sending and receiving station, and they take advantage advantage of the broad reach of ordinary telegraph service. One would ordinarily prefer direct picture transmission where possible, because it is more economical and can be done in shorter time. But where direct phototelegraphy is uncertain or impossible, e.g., because of distance, then the indirect method should be used.

korn_fig28.jpg korn_fig28a.jpg korn_fig28b.jpg

Fig. 28. Telegraphische Übertragung einer Photographie mit Hilfe von Buchstaben telegrammen (Rom - New York 1922).
ex Korn 1927

Above is an example of a phototelegram. The orginal has been analyzed in what appear to be five classifications of tone -- hence four diameters of dots plus blank space -- coded, committed to punched-tape intermediate record, and transmitted from Rome to New York in 1922.

The analysis would likely have been done by a selenium photocell, feeding varied currents to five tuned relays controlling a tape punching mechanism.

The image is shown at three different sizes, to suggest how easily but five grayscales can approximate the tonalities of a halftone image.

Bartlane system (1921-35)
Harry Guy Bartholomew, Maynard Leslie Deedes McFarlane

Taken together, the Bartlane patents chronicle a gradual move to full automation of "exploration," analysis, encoding, translation to an "intermediate record," and reconstitution at the receiving station. Yet it is not easy to derive the definitive Bartlane system from the various Bartlane patents, so numerous are the patents themselves, their claims, their "examples" of arrangements.

The patents suggest a certain tentativeness in the undertaking, constant tinkering with prototypes. The use of five-unit punched tape doesn't necessarily mean 32 variations of tone: it might mean four tones and eight counts; or the rows of holes and the opacity of the (blackened) tape itself might together serve as light-valves and masks, respectively, for physical exposures of five strengths. There was ambivalence about code versus modulation over ordinary phone lines; the intermediate record might actually be a half-tone image functioning as a wax audio record for transmission as sound. And then there are the differences between US and British versions of what are more or less the same ideas: the American versions, typically a year or two behind, might present evolved and/or miss suppressed ideas. All of this is to suggest that the patents start looking like rough drafts and versions of the same work of art, itself always receding.

McFarlane writes, about this work, that "...the only way to tell if a change represented progress was to make a picture and judge from inspection of the result... Looking back from the confines of a well-equipped electronics laboratory, it seems astonishing that any progress was made fifty years ago." (1972: 770)

The Bartlane System is described by Marius Rensen at

bartlane_type_2a.jpg bartlane_type_2b.jpg

"In 1921 a telegraph printer with special type faces reproduced this picture from a coded record."
Fig. 1 and caption ex McFarlane, "Digital Pictures Fifty Years Ago." Proceedings of the IEEE 60:7 (July 1972)

Detail of same. Pattern reminiscent of "crochet" types of the 19th century.

Above method was "abandoned in favor of parallel development of an off line photographic reproduction" yielding improved picture quality.

Bartlane patents GB

1921 GB 166,917
Improvements in and relating to the production of facsimiles of documents, pictures, drawings and the like.
"Presuming the code comprises letters and numbers, and reads, for instance, A 4 B 2 D 1 E 6 etc., the successive areas will be exposed as follows, 4 areas tone A, 2 areas tone B, 1 area tone D, 6 areas tone E, etc." (2/64ff). The tape operates a shutter device that can either provide multiple exposures of equal lengths, or explosures of varying duration. Drawings relate primarily to the shutter mechanism.

1923 GB 195,577
Improvements in and relating to telautography or phototelegraphy "In picture transmission to obtain gradation of tone in the reproduction, a plurality of representations from the original, each corresponding with a given fraction or range of tone, are transmitted, and the corresponding received representations are used to form a composite reproduction of the original. An intermediate record of the tone variations, such as a perforated tape, may be used, and such record may be effected by the method and means described in Specification 197,402."
substantially same as 1927 US 1,653,425

1923 GB 197,402
Improvements in and relating to telautography

1924 GB 209,816
Improvements in and relating to Telautography or Phototelegraphy
(optical system, using elaborate lenses and five-unit tape as a kind of light valve; same as US 1924 1,674,881)

1924 GB 226,244
Improvements in and relating to Telautography of [sic] Phototelegraphy
(multiplexes telegraph lines, or uses telephone transmission)

1926 GB 262,943
Improvements in and relating to telautography or photo-telegraphy
readers scan slightly off in successive scans, so as not to miss thin features
similar to 1930 US 1,758,388

Bartlane patents US

1923 US 1,454,719
Facsimile transmission system
substantially same as 1922 GB 182,928
A representation of the matter to be transmitted, such as a half-tone or other etched plate or an impression in wax such as is used in phonograph records, is used to control production of sound signals corresponding with the elements to be sent, and the sound signals are transmitted by line or wireless telephony. At the receiving end, the signals are used to control the reproduction. (from UK abstract)
The sound produced by the relative motion between the surface on which the representation is formed and the jewel or needle will vary in character according to the size of the dots when the representation is in the form of an etched metal plate..." (1:47ff)
no coding

1925 US 1,545,301
Telegraphy combined with phototelegraphy or telautography
devoted to allocation of image and message signals in various channels of multiplex systems, for efficient use of circuits

1927 US 1,653,425
substantially same as 1923 GB 195,577
Here is a clear statement of the initial Bartlane system, in which four or five different representations of a single image are made, each comprising a different tonality (deepest tone, next lighter tones, still lighter tones) which are coded and transmitted separately, for "composite reproduction" at the receiving station. Four "examples" are given :

  1. (1) four representations are formed on zinc plate (by coating with an insulating material), wound round spindle, explored. signals stored on perforated tape.
  2. Record stored on tape. Perforations themselves control exposure.
  3. Scan of a half tone or line screen reproduction, code record stored on perforated tape.
  4. Similar to example three, except that it incorporates a Western Electric 6A machine perforator.

1928 US 1,674,881
Telautography or phototelegraphy
The perforated tape itself provides light valves (in concert with lenses and apertures, "such apertures being wider at one end 10a than at the other 10, the narrower end being adjacent that over which the hole representing the lightest tine will pass." (1:81ff)
substantially same as 1924 GB 209,816

1929 US 1,731,518

1930 US 1,758,388
involves five successive scans of same image, with a "progressive 'lateral' variation of the reader points" in order to capture subtle details. perforated tape is light valve.
substantially same as 1926 GB 262,943

1930 US US 1,754,688
Machine for reproducing and transmitting pictures

Bartlane : perforated tape -- the "intermediate record"

1929 US 1,731,345
1933 US 1,910,556
1935 US 1,910,586
1935 US 2,021,474

Harry Guy Bartholomew (London), Maynard Leslie Deedes McFarlane (New York)

The following patents are grouped together, out of chronology, because each of them directly relate to coding and efficient use of tape -- that is to say, data compression.

1929 US 1,731,345
Method of and tape for reproducing pictures or the like

The first -- 1929 US 1,731,345 -- sets the stage. A first intermediate record is normal five-unit punched tape. As explained in the note to Fig. 10, it can describe as many as 32 tone values, but 10 are shown here. This perforated tape is fed through an apparatus shown in section in Fig. 4, which contains condenser lenses and the apertures (5), which can be adjusted to yield the "area relationships" shown in Figs. 6 and 7. It is the combination of these five apertures, with their varying widths, that yield up to 32 gradations of tone.

Note that each row of code in the perforated tape contains information for one "small area" at a time. One hundred such "pixels" in a row would, therefore, require 100 rows of 50-unit code. Subsequent Bartlane patents provide for "counting" of adjacent small areas with the same tone value, as a savings in tape running time (and hence, cost).


Fig. 6 above

"As shown in Fig. 6, the shutters 20 are adjusted so that the five separate apertures in the openings 5 formed thereby have the area relationship indicated by the Circles A, B, C, D and E in Fig. 6. As shown by the graph 35, the relationship between the respective areas of the said five perforations A-E inclusive is substantially linear. Hence,if a certain area of the picture to be reproduced is very dark, almost a pure black, and only a single perforation is formed in the record tape, the location of this perforation corresponds to the opening A, so that when the tape of a duplicate thereof is passed through the appratus shown herein [Fig. 4], only a small amount of light passes to the light-sensitive film. Likewise, when the picture has the next gradation or tone value at a given area thereof, so that two perforations are formed in the record tape, these two perforations will control the apertures A and B. Experience has shown that by thus regulating the light which falls upon the light sensitive-film, that a much more accurate reproduction can be formed." (2:108ff)

Figs 9 and 10, at right

"In the embodiment shown in Fig. 10, the two perforations shown in the third transverse line represents the third tone value, the single perforation shown in the fourth row respresents the fourth tone value, and so on, until nine tone values are represented, the tenth tone value, which is absolute black, being indicated by the total absence of all perforations. By suitably choosing the permutations of the five message perforations, a maximum of thirty-two tone values can be recorded, but the recording of ten tone values has been found sufficient for practical purposes." (3:33ff)

Fig. 7 above

"As shown by graph 35' in Fig. 7, the relationship between the apertures A', B', C', D' and E' is expressed by a graph having different inclinations at the ends thereof with respect to a horizontal axis. ¶ It can be seen from Fig. 7 that the location of a perforation or perforations shown in Fig. 7 substantially affects the amount of light shining upon the reproducing film." (4:71ff)


1933 US 1,910,556
Mechanism for producing a perforated tape for reproducing pictures of the like
This patent and 1,910,586 focus on coding of the grayscale images in their successive "zones." Neither is concerned with the actual method of scan, whether relief or photocell, but with the translation of that data into code. The present patent does provide for the use of the punched tape for exposure of light, through 1, 2, 3, 4 or 5 of its apertures, onto photocemical paper.
no counter

1933 US 1,910,586
Telautography or Phototelegraphy
Incorporates counter.
"The object of the present invention is in general to enable the time occupied in transmitting a record of the picture to be reduced... the results of analysis of the original to be transmitted are divided into two portions, one indicative of the tones and the other expressing the number of times each tone occurs in succession." (1:47ff)
Several means of coding this information, on either one or two intermediate records -- if two, the primary intermediate record for "tone perforations" and the secondary intermediate record for "count perforations." (14:5ff) Provides a thorough exploration of getting the most out of five-unit tape, particularly with regards to the tradeoff of tones versus count. See for example 4:33ff (and Fig. 4) where six tone combinations are indicated by three positions, leaving two positions available for count (maximum 4); versus Fig. 6 four tone combinations (two holes) leaving room for eight counts (in three holes).
"Fig. 7 is an elevation of a Western Electric 5B start-stop distributor modified to act as a counter and sequence switch for an apparatus to automatically punch a secondary intermediate record from a primary intermediate record." (3:4ff) compare to Watson and Weaver, "Electrical Transmission of Pictures," 1926 US 1,602,469

1935 US 2,021,474
Presents punched tape intermediate record as a means of controlling against unintentional fluctuations or fading attendant encountered in "direct" photo-telegraphy and television (calls to mind the same objective in Reeves's 1942 patent for pulse code modulation in telephony).

Bartlane : image analysis

1929 US 1,731,345
1933 US 1,910,556
1935 US 1,910,586

Harry Guy Bartholomew (London), Maynard Leslie Deedes McFarlane (New York)

By ingenious means described in
1923 GB 197,402
1923 GB 195,577 and
1930 US 1,758,388
each segment of five units on the black (not white!) perforated tape functions as a series of five light valves, allowing the passage of up to five beams of light in combinations of 1, 2, 3, 4 and 5 open perforations, for exposure on photographic paper. The system incorporates a series of lenses, all training the light source whether various or single onto the same target point. The point here is five tones -- this would later be extended to 16.

The analysis of the image

1,758,388 (1930) introduces a "progressive 'lateral' variation of the reader points...from what may be termed the standard position." The Bartlane system creates five prints, each of which is exposed "for varying lengths of time to the action of light... one of these prints, which may be called the first print, and which is exposed for the shortest period of time, only records the brightest tones of the picture to be reproduced, the second print records the tones of the first print and in addition the next brightest tones, etc., until the last print records ubstantially all of the tones of the picture to be transmitted. As stated in [195,577], these prints are formed upon a metal plate by means of a film of hardened gelatin, which acts as an efficient insulator."

In order to secure perfect recording or transmission of the tone values of a print, it would be necessary for the pitch of the said helical path to be equal to the width or diameter of the reader point. This, however, is impossible for a number of practical reasons, and in actual practice it has been found necessary to impart a definite pitch to the said helical path so that the reader points do not pass over each and every consecutive small area of each print. This results in a noticeable loss of detail when the reader points simultaneously contact with corresponding small areas of the respective prints, which has been the practice up to the present time.

According to this invention, the reader points are placed so as to simultaneously contact with corresponding small areas of the respective prints, these different small areas comprising a consecutive series.

For example...

1,758,388 is, apparently, the same as 1925 GB 262,943 -- which however has different (more specific in some aspects, less in others) language but includes no drawings. [this is a problem that is addressed as well by Ranger in his important 1926 paper] See a paper by Wise and Coggeshall in Proceedings of the IRE (May 1941), usefully summarized here.

UK Patent No 195,577
application : 19 September 1921
complete left : 23 May 1922
accepted : 19 March 1923

Improvements in and relating to Telautography or Photo-telegraphy

Harry Guy Bartholomew (London), Maynard Leslie Deedes McFarlane

A primary objective of this patent is the elimination of human agency in coding and decoding, by means of sounds from intermediate records on wax cylinders. It does not describe in detail the analysis or initial "exploration" of the original image, for encoding.

"A further object of the invention is to provide an improved method of securing the desired graduation... This phase of the invention comprises forming a plurality of representations from the original, differing one from the other in that they each correspond to given fraction of the tones or ranges of tone in the original.

"Thus one representation may comprise only the deepest tones or full shadows of the original, a second may include only the next lighter tones or both these tones and the full shadows, a third including still lighter tones and so on.

"Four or five such representations will usually be found sufficient, and by their aid a plurality of prints may be produced in register on a single surface in order to provide a final result which shall sufficiently for most practical purposes agree with the gradation in the original." (2:104ff)

Moreover, "The object of the employment of the intermediate record is to facilitate the correction or errors which may arise..." (5:25ff)


UK Patent No 257,013
application : 24 February 1925
complete left : 24 December 1925
accepted : 24 August 1926

Improvements in or relating to the reproduction of pictures, drawings and other representations by the aid of telegraphy

Creed & Co., Ltd. and Frederick George Creed


"...For this purpose, a Wheatstone transmitter may be used, which, owing to all the perforations x in the tape being on one side of the row of feed holes B therein, will have one of the peckers, say the negative pecker, ordinarily used in such a transmitter, omitted. In this case a dot signal will be transmitted for every perforation x punched in the upper portion of the tape." (9:95ff)

"The receiving and printing apparatus used may conveniently be of the kind described in the Specification of our Letters Patent No. 228,842, but the printing wheel used in such apparatus, will require a few printing levers, namely six in the example now being described, each provided with a different sized pin or projection for printing dots, the different sizes of the dots so printed corresponding in area with the different densities in the original picture..." (9:104ff)

The elementary signs here are six dots, of six diameters. Presumably a seventh signal -- either "a" or "i" on the Wheatstone tape Fig. 6 -- would cause a blank (white) dot space. Their progressively stepped diameters distinguish these dots from half-tone dots, whose diameters can be any size.

We come here nearly full circle to the ideas embodied in Montagna, Mortier and Ellero, and as far back as Carl Fasol who achieved wonders with but four or five dot diameters.

This patent is substantially the same as 1929/US/1,713,266.

US Patent No 1,851,072
application : 15 December 1923
patented : 29 March 1932

Apparatus and method for electrical transmission of pictures

Gilbert S Vernam, Edward F Watson and Donald B Perry, assignors to AT&T


"Another object of our invention has relation to transmitting a single code combination for a sequence of elements of like shade, the combination indicating both the degree of that shade and the number of elements in the sequence." (1:9ff)

"The receiving and printing apparatus used may conveniently be of the kind described in the Specification of our Letters Patent No. 228,842, but the printing wheel used in such apparatus, will require a few printing levers, namely six in the example now being described, each provided with a different sized pin or projection for printing dots, the different sizes of the dots so printed corresponding in area with the different densities in the original picture..." (9:104ff)

"If a shade recurs more than seven times in succession a punch will be made on the seventh count and the count will be begun again for another series." (2:123ff)

Several patents relate to counting elements of a similar shade, and coding that count in combination with the respective shades. Gaynor (1922/UK/190,522) describes a cipher code system in which "the last nine consonants (N, P, Q, R, S, T, V, X and Z)" indicate the number of times a value is repeated along a scanning line. Of course, it takes five letters (each one composed of a five unit code) to yield a five-letter cipher, making this a relatively inefficient means. See also Bartlane 1921/166,917 and 1933/1,910,586 (which allows for up to 32 tone values).

I show Fig. 2 because it so clearly expresses the relationship of the five unit code (with its 32 possible combinations) and efforts to exploit it to economize on tape length (hence transmission time and expense).

Five-unit tape limits the number of elemental signs that can be easily used describe a picture. That limit is not absolute, however; see for example Bartlane 1930/1,758,388 and 1934/GB/404,715. Their 1934 specification explores the tradeoffs in five unit code of, say, six tone combinations (three holes) and maximum four positions (two holes). Electrical Research Products (1934/GB/404,715) provides for 16 values (but does not address "count").

scrambled pictures


UK Patent No 655,320
application filed : 17 December 1947
complete : 18 July 1951

Facsimile Telegraph Systems

Standard Telephones and Cables Limited



"A receiver so arranged as to have its printing unit or mechanism move along the paper on which the message is to be printed in accordance with the same codes as those used at the transmitter will print said message 'in clear,' but any other receiver, the printing mechanism of which be not so arranged as to execute the required movement, will print scattered dots and dashes giving no intelligible character." (1:70ff)

Scrambles pictures for secure transmission, by (1) employing variations in speeds of scanning (first line, second line and so on) and (2) interlacing (move ahead four, move back eight); requires synchronization between sending and receiving machines.

Other example of image scrambling devices include 1922 GB 153,597, 1931 GB 354,249 and the much-later 1951 GB 655,320. Scrambling devices are similar in some ways to (1) condensers, that convert figure series into alphabetical ciphers, and (2) to various encryption devices that emerged out of multiplex printing telegraph technology (Hebern, Sanford Vernam, A G Damm, Ingenieursbureau "Securitas", etc.). (e.g., 1922 GB 153,597, 1931 GB 354,249 or the later 1951 GB 655,320)



US Patent No 1,503,590
application : 13 June 1922
patented : 5 August 1924

Method and system for transmitting pictures to a distance

Eliot Keen


"This will give in the last analysis a picture composed entirely of fine sunken (or raised) parallel lines, all of substantially the same width and spacing, but varying in length and grouping. This form, the preferred one, but which may be infinitely varied without departing from the spirit of this invention, leaves the final plate used for transmission a mere series of fine corrugations on even centers and of varying length. The bands referred to have in this embodiment no final tangible existence as such, being merely successive groups of lines or of spaces where lines might be. Thus, in dark areas of the picture, assuming numerical groupings as shown on the drawings, a band would comprise seven fine lines; in areas a little less dark, five, centrally located; in gray areas, three; in light areas, one fine line; and in white areas, no lines at all." (1:45ff)

At receiving end, vibrations control light beam through lens light-valves onto photographic paper. Perhaps the most important feature of this patent is the synaesthetic idea of translating a picture into sound; other patents on this page translate a picture into code -- a form of ekphrasis.

Keen appears to have been an illustrator ca 1900-1920, and has several other patents under his name, including :
1916/1,176,147 Telegraphy (transmission of pictures, emphasis on diaphragm at receiving end)
1916/1,176,148 Telegraphy (full system, incorporating a slightly different diaphragm apparatus)
1918/1260393 Apparatus for producing animated drawings (ccl/352/87).

4 august 05