In my earlier post on the "Electric Dog" by Miessner and Hammond (here), I commented on some uncertainty regarding Miessner's and Hammond's relationship together, and as to whether or not there may have been another dog built. This was as a result of how the newspaper and magazine articles were reporting on the "electric dog".
I finally got around to getting a copy of Miessner's book "On the Early History of Radio Guidance", published in 1964.
In 1957, in the proceedings for the Institute of Radio Engineers No45 pp1191-1208, there was an article written by John Hays Hammond Jr., together with E.S. Purlington titled "A History of Some Foundations of Modern Radio-Electronic Technology". The image below is from that article.
This article covers many aspects of Radio-Electronics, but for our purposes here we are only interested in Radio-Guidance and the "electric dog". In essesence, claims were made around secret work and Hammond's patents on radio-guidance, all without a single reference to Miessner himself. There was a bit of controversy at the time, but Miessner remained quiet, until 1964 by way of publishing his book.
In the book, he describes Hammond's sketch diagram of a phototropic vehicle. Hammond was influenced by Loeb's writings on "trophism".
Hammond goes abroard, and leaves Miessner and an assistant mechanic, Joseph Broich, to build the machine. Miessner had already outlined a similar device, in tracking a searchlight for a torpedo. So with Hammond's brief, Miessner and Broich designed and constructed what was later to be called the "electric dog".
Compare with Patent 1,387,850 by Hammond filed Apr 1912. see here.
Hammond's and Miessner's relationship deteriorated somewhat, and Miessner left Hammond's employ and went back to school. In wishing to demonstrate the model, Hammond allowed Miessner to borrow this obsolete piece of technology. Miessner describes the lecture series which so popularised the "electric dog".
So, there was only one dog, Hammond initiated and funded its development, Miessner refined the design and built it with Brioch in 1912, and Miessner later borrowed it.
[Note: also significant in the below is a transcript of a letter from Nikola Tesla to Miessner on Teleautomatons.]
Below are the relevant text extracts from Miessner's book.
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….. it would appear that Hammond's technical background was very limited indeed at the time. This view is reinforced by a plaintive query I received a few days later.
Hammond to Miessner, March 1, 1912:
As I understand, in the order of the General Electric Co. you intend to excite the fields of the low frequency, thousand spark frequency, generators with the high frequency alternators. This will give the effect of producing a 500 cycle note at the receiving station. Each of the 500 cycle circuits will in turn be composed of higher periodicities which are produced by the high frequency alternators. Explain the principle of this in your next letter a little more definitely.
A great many of Hammond's conceptions, given to me orally or by letter, were so crudely or wrongly put that they required invention on my own part to give them any meaning at all.
Hammond to Miessner, March 19,1912:
I have here enclosed a sketch of a proposed method of multiplex telephony, which if allright I wish you to submit to Mr Austin … Also include in my Orientation patent the idea of stopping the machine by the intensity of the light.
But more often the procedure was reversed and ideas went from me to Hammond and then to the patent attorneys.
Hammond to Miessner, March 23, 1912:
I would suggest your sending me your descriptions of the System of Selective Multiplex Wireless Telegraphy and Telephony and the description of the undamped waves of the periodically varying amplitude and the description of the Orientation System. I will go over these carefully and draw up claims for them and forward them to Austin.
I have said enough to show that during this entire period, far from actively undertaking laboratory work or even acting as my collaborator,
EARLY HISTORY OF RADIO GUIDANCE p13
Hammond was not even present in the laboratory except for brief visits; his relationship to the technical work being carried on was rather that of an absentee entrepreneur. In the spring of 1912, he actually left the country, having been appointed a member of the U.S. delegation to the International Radiotelegraphic Conference in London. I saw him off: there is a snapshot of the two of us on board his ship in New York harbor (Fig. 3). Besides going to London, Hammond managed to contact every important expert in Europe. From London he wrote me (on Conference Radiotélégraphique Internationale de Londres stationery, under the date le 4 Juillet) that he had already been in touch with "Count Arco, Majorana, Ferrie, Dr. Goldschmidt, Marconi, and Duddell, Erskine Murray, Prof
3.—Snapshot of author (right) and Hammond taken on day of Hammond's departure for England in June 1912.
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Flemming and others. I have a stack of papers … that will fill a trunk … I am in touch with Zenneck … keep all of this to yourself."
It was during this period that I conceived, designed, and supervised the construction of an entirely new torpedo-control system and apparatus, utilizing known principles where possible and inventing new features as necessary. It was very fortuitious for me that the work was carried on in Lowenstein's laboratory, for I certainly learned a lot from him while spending nearly half of my time helping out on his own projects. On the other hand, Lowenstein participated relatively little in the work that was being done in his laboratory for Hammond, which was left almost entirely to me. In addition to the above-mentioned torpedo-control system, I also originated and designed many circuits related to the development of a jam-proof radio transmitter-receiver system.
First, I constructed four vacuum-tube assemblies (designated by Lowenstein as "ion controllers") for general experimental use. Their first application was in replacing the motor-driven, commutator-type dc current interrupters for tests on an of beat-type selective system that I had also designed. Tests with the audio-beat system proved to be very successful, albeit with a beat-tuned reed relay, but to some extent also with a beat-tuned LC circuit, followed by detector and a de relay. The main problem of close-range interference by enemy rf transmitters was not yet solved in practice; such interference could lock on the torpedo-control receiver and render the desired control ineffective.
Second, I increased the sensitivity and reliability under extreme vibration of the Weston microammeter relay by substituting a storage-battery-excited electromagnet for the permanent magnet (quadrupling sensitivity) and improving the contacts: a pointed platinum contact replaced the button contact on a moving arm, and a mercury globule covered by an oil film (to limit oxidation) replaced a fixed platinum contact element. The design was quickly carried out: my notebook shows that it was conceived and first tested in mid-February, with final tests taking place on March 1, 1912. (This instrument, which later accompanied me to Gloucester, attracted the attention of all who saw it; I well recall overhearing Dr. G. W. Pierce of Harvard University, when he first visited us at Gloucester, saying to Hammond that he would "take off his hat to the man who made that.")
Next, I designed and constructed a rotary stepping switch driven by an electromagnet, a crucial element in starting, stopping, or reversing the direction of rotation of the steering motor's armature-current control. A microammeter relay controlled a more powerful relay in the magnet circuit, which in turn controlled the pawl-and-ratchet device. The final design was carried out by Frederick Pierce Co. at 18 Rose Street in New York City.
EARLY HISTORY OF RADIO GUIDANCE p15
An even more important component that I designed and saw through construction was a motor-power relay with an adjustable time delay. This device involved a solenoid with a sliding core connected to a piston in a pneumatic dashpot fitted with an adjustable needle-valve air inlet and a spring-biased flapper-type valve for quick exhaust. An extension spring at one end served to return the core quickly to its normal position. A contact point on the opposite end of the core connected to a fixed contact; these contacts were in series with the armature circuit of the steering motor and the battery. After the stepping switch had selected the correct armature rotation direction, no current would flow until the time-delay switch finally closed the armature circuit ; but the field winding of the motor remained always energized.
This was a very necessary device, for the following reason. If the rudder was set, say, for a half-starboard position, and the steering motor was stopped because the stepping switch was in an "off" position, the stepping switch would have to go to a reverse (i.e., port) rudder position before it could go through the next "stop" and onto the following starboard rudder position. (The stepping switch ran in a continuous repetitive sequence, off—starboard—off—port—off—starboard, etc.) The time-delay relay simplified the operation, since short impulses did not switch on the current to the motor armature, so that any intermediate positions of the stopping switch could be, so to speak, skipped.
I also devised a mechanism driven by the steering motor via a flexible shaft; this device acted as a limiting switch for the steering motor, permitted setting of the rudder at the "dead center" position, and controlled flashing signal lights that indicated rudder position; and I designed such details as a worm drive and a clutch for the steering motor, so that it could be used in conjunction with a conventional steering wheel and be manually coupled to it or decoupled from it.
Finally, I designed and constructed an automatic photoelectric orientation mechanism for the purpose of demonstrating the "homing" type of guidance system. This apparatus, which became known as the "electric dog," attracted much attention; it is shown as Fig. 3 of the Hammond-Purington paper.'
It was during this period that I also conceived and designed, but did not carry through to construction, a stationary type of automatic orientation mechanism for mounting on a moving vehicle or boat. A rotating circular table of the "lazy Susan" type carried a motor with a pinion meshing with a stationary outer circular rack. The turntable also carried two condensing lenses separated by an opaque screen, and a selenium cell behind each lens. The entire apparatus was enclosed in a weatherproof housing through which the "eyes" looked outward. The device was intended for use with my fixed-frequency, amplitude-modulated, infrared
p16 BENJAMIN FRANKLIN MIESSNER
control system and would serve to keep the "eyes" always facing the control searchlight as a sunflower faces the sun, to avoid the possibility of enemy searchlight interference. Moreover, the control searchlight would be af-modulated mechanically to prevent stray interference by sunlight, or 120-cps-modulated electric light, and thus to permit daylight operation. In his letter to me of March 6, 1912, after acknowledging receipt of my progress report on this device, Hammond concluded by saying, "I also approve of your method of light orientation." (Previously, on Feb. 5, 1912, he had authorized purchase of the searchlight and other apparatus for this control.)
I even devised another method of modulating the electric-arc searchlight, using 500-cps ac instead of dc. Instead of using a large inductance to sustain the arc, I planned to use a small high-voltage step-up transformer to charge a high-voltage condenser that would periodically discharge across the arc carbons, as in a spark gap. (Choke coils were included to prevent the rf discharges from passing through the generator.) The primary current of the step-up transformer would be fed through a phase-advancing capacitor adjusted so as to cause the rf spark discharge across the arc carbons to occur when the primary current was passing through zero, so that the rf spark discharge would prevent extinguishing of the of arc current, which would ride across on the rf discharge. (I never did get around to testing this scheme during my work with Hammond, but I did test it a few years later at the Kearney power plant of the Public Service Co. of New Jersey, when I was employed by E. J. Simon, Inc. These tests were carried out with the help of William Siebenmorgan, a consultant to Simon who was very much interested in electric arc welding. The high currents and low power factors inherent in the use of arc welders, in which a large inductance is used to sustain the arc, were anathema to the power companies and we were encouraged to develop my alternate scheme; but although the tests were successful, we did not carry them very far. A similar scheme was later patented by others and I understand is in considerable use today.)
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But my misgivings regarding the motives that had inspired this offer were not dispelled; I wrote him refusing the offer and telling him that I intended to publish my own investigations and inventions. I concluded by saying, "I wish to assure you that my intentions in publishing the results of work which is original with me are not to injure you, but merely to get whatever credit may be due me for original work."
Hammond still endeavored to keep a door open: a letter he wrote me on April 12, 1913, closed with yet another offer: "If I am still in wireless work after you complete your studies at the University I will always be glad to offer you a good position."
During 1913-16, I attended Purdue University, a rather advanced student in some subjects, but quite unconcerned with others. On Oct. 15, 1913, soon after I started college, I gave a paper before the Purdue University branch of the AIEE, describing the radio-controlled torpedo work that, together with an account of all known prior art, had been also the subject of my article in the Scientific American of July 20, 1912. (A description of the lecture appears in Proc. AIEE 33: 21-22, 1914.) In a later lecture, a fascinated student body and faculty watched a demonstration of my light-control methods, including the aforementioned "electric dog," which Hammond had loaned me for the purpose. This device created a great deal of interest and I was asked to give three more lectures on the same subject. One was given in Indianapolis, before the Purdue-Indianapolis section of the AIEE. The second lecture was given at the Chicago Electric Club, where I made expanded demonstrations that included my "electric thief catcher." The third one was for charity: a brief demonstration of the electric dog, of remote firing of a pistol by a light beam, etc., made at the Auditorium Opera House; as part an Associated Charities minstrel show sponsored by the public utilities companies of Chicago. The electric dog caught the public fancy and newspapers throughout the country reported on it.
This device had been originally constructed on the basis of a two-page letter containing a rough sketch from Hammond, dated March 2, 1912. Hammond had been much taken with the writings of Jacques Loeb, the famed Rockefeller Institute biologist, who had proposed various theories explaining many kinds of trophism—for example, why moths fly into flames. Hammond thought that an analog device could be embodied in a photoelectrically activated mechanical contrivance on wheels containing its own motive power and a steering device (a turning rear wheel). It was my job to translate this sketchy concept into a workable, demonstrable device, and I did so, with the able assistance of Lowenstein master mechanic, Joseph Broich.
Hammond's original proposal (Fig. 9) was based on two selenium cells "eyes" separated by an opaque screen, each operating a relay. The two
p38 BENJAMIN FRANKLIN MIESSNER
relays controlled currents (from separate batteries) used to energize two solenoids, pulling oppositely on a centrally and vertically pivoted arm on which a tricycle-like steering wheel was mounted at the back end of the contraption. Hammond showed the two front wheels geared to a propelling motor for the machine.
Hammond seemed untroubled by the fact that sensitive relays would be necessary for use with selenium cells and could not be used to control the current in the steering solenoids directly. Nor did he worry over the fact that an automobile-like differential was required for the drive wheels and that the two solenoids were always pulling against one another for mastery of the position of the steering wheel. He did show adjustable series resistances in each of the solenoid circuits, perhaps in a vague hope that their pulls could be somehow balanced for the dead-center position, with the light shining into both "eyes." Once again, a considerable amount of inventing on my part and design work by Broich was necessary to construct a workable device, which turned out to be quite different.
As I mentioned previously (see p. 16), even before receiving Hammond's suggestion, I had already made selectivity tests on my modulated-light ideas, and on March 11, 1912, I sketched out my plans for the orientation mechanism that would keep a torpedo's "eyes" always facing the controling searchlight (Fig. 10). Since those days, the principles involved have been, of course, widely applied for missiles of the homing type, as well as for remotely guided missiles; for automatic guidance of celestial photographic telescopes; and for satellite tracking. The fixedfrequency-modulated infrared signaling system has also been applied to "invisible fences" for intruder alarms around factories, banks, etc.
fig. 10.—Notebook entry dated Mar. 11, 1912, showing my plan of an "orientation mechanism" for torpedo control. Central table rotates to keep "eyes" facing controling searchlight.
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AN EARLY TEXT ON RADIO CONTROL
While still an undergraduate, I published a book (Radiodynamics, D. Van Nostrand Co., New York, 1916) of 200 pages and containing 112 illustrations, in which most of the "preliminary work" that the HammondPurington paper so blithely passes over is described in some detail, together with an account of all earlier known work on the same subject. The book is something of a rarity now outside of libraries: only 1100 copies were printed. Hammond tried desperately to stop its publication, by intimidating the publishers and myself, and by appealing to the War Department on grounds of security. The publishers questioned me about the propriety of disclosing Hammond's "secrets," and in a letter to Charles E. Speirs of Van Nostrand I sought to reassure them.
Miessner to Speirs, Aug. 14, 1915:
As to the laboratory secrets of my former employer, I would be foolish in hazarding my own reputation and future career by revealing anything which I was not entitled to speak, and have limited my manuscript accordingly. Moreover, M(r). Hammond not only knew that I was to lecture and write along this line, but approved of the same and supplied me with both material, experimental apparatus [the "electric dog"] and photographs for this purpose. On this point he wrote me on Oct. 11, 1913: "You may mention any of the points which you recorded while working here. These matters are now obsolete and I do not believe that their disclosure would have much bearing on my work."
With my letter, I enclosed blueprints of two letters from Hammond relating to my proposed publications and confirming that he was aware of my plans and eager for me to describe and picture the early work in his laboratory during my time there.
I also wrote to Gen. Weaver, chief of U.S. Coast Artillery, to whom we had made our control demonstrations in late 1912, and offered to submit my manuscript to him for editing. General Weaver begged off, saying that he did not feel equal to the task, but he suggested that we should submit the manuscript to Hammond for possible deletions. In the meantime, Hammond wrote to Van Nostrand asking for permission to look at my manuscript and threatening suit if any of "his" details were made public.
EARLY HISTORY OF RADIO GUIDANCE 43
Accordingly, Hammond was invited to see the manuscript at the Van Nostrand offices in New York, an invitation that he accepted with alacrity. Speirs wrote me afterwards that Hammond had exhibited an "attitude which was rather imperative." Speirs himself felt that "whatever we do is more as a. matter of courtesy than right, and it is quite apparent to me from his letters to you that you have his permission to do precisely what you have done." Hammond wrote out a page of criticisms, which Speirs sent on to me, and which ended with another threat of legal action.
Hammond to Speirs, Feb. 26, 1916:
… I wish to state that my letter to Mr. Miessner authorized him to describe the work up to the time that his services ended with me at my laboratory. This he seems to have done fairly exhaustively. Any information which he may have been able to obtain later than that time concerning my work which he attempts to publish will be taken by me as grounds for legal suit, and I am confident that I shall have the backing of the government in the institution of such a suit.
I have shown this book to present-day experts and have been told that the only reason why it did not go beyond a single printing was that the material was far ahead of its day. It is interesting to note that the publishers' reader thought that my manuscript was well done, but felt that some of my statements might sound "over sanguine" to some readers. In the light of later developments in radio control and guidance, he need not have been so diffident.
I am almost certain that the reader who reviewed the book for Van Nostrand was none other than Nikola Tesla. Since I was planning to include descriptions and drawings of his pioneering efforts in the field of automatic control, I had written to him, only to find that he was already well acquainted with my project. We exchanged three letters in all, the first in September 1915. (The originals of his letters are in the Manuscript Division of the New York Public Library.)
Tesla to Miessner, Sept. 29, 1915:
Your favor of September 24th has been received in due course and has interested me in view of your forthcoming book on "Radio Dynamics". Some time ago my friend, Charles E. Speirs of the D. Van Nostrand Company, told me that you were engaged in its preparation and I commended it for publication as very little has been written on the subject …
I am naturally greatly absorbed in this field of invention which has been barely touched and which I look upon as extremely promising. In an article in the Century Magazine, copy of which I am forwarding to you, I have related the circumstances which led me to develop the idea of a self-propelled automaton. My experiments were begun sometime in '92 and from that period, on, until '95, in my Laboratory at 35 South Fifth Avenue, I exhibited a number of contrivances and perfected plans for several complete telautomata. After the destruction of. my Laboratory by fire in '95, there was an interruption in these labors which, however, were resumed in '96 in my new Laboratory at 46 East Houston Street where I made more striking demonstrations,
44 BENJAMIN FRANKLIN MIESSNER
in many instances actually transmitting the whole motive energy to the devices instead of simply controlling the same from distance. In '97 I began the construction of a complete automaton in the form of a boat, which is described in my original patent specification 013,809. A copy of this, also, is being forwarded under separate cover. This application was written during that year but the filing was delayed until July of the following year, long before which date the machine had been often exhibited to visitors who never ceased to wonder at the performances. The drawings of this specification were made from this machine to scale. In that year I also constructed a larger boat which I exhibited, among other things, in Chicago during a lecture before the Commercial Club. In this lecture I treated the whole field broadly, not limiting myself to mechanisms controlled from distance but to machines possessed of their own intelligence. Since that time I have advanced greatly in the evolution of the invention and think that the time is not distant when I shall show an automaton which, left to itself, will act as though possessed of reason and without any wilful control from the outside. Whatever be the practical possibilities of such an achievement, it will mark the beginning of a new epoch in mechanics.
I would call your attention to the fact that while my specification, above mentioned, shows the automatic mechanism as controlled through a simple tuned circuit, I have used individualized control; that is, one based on the co-operation of several circuits of different periods of vibration, a principle which I had already developed at that time and which was subsequently described in my patents #723,188 and 723,189 of March, 1903. The machine was in this form when I made demonstrations with it in 1898 before the Chief Examiner, Seeley, prior to the grant of my basic patent on Method of and Apparatus for Controlling Mechanisms at a Distance. [My italics.]
In my experiments and investigations in Colorado from 1899 to 1900, I developed, among other things, two important discoveries which will be essential in the future development of telautomatics. They are described in my patents #685,953 and 119,732 which were taken out at a later date. These two advances make it possible to supply to an automaton great amounts of energy and also to control it with the utmost accuracy when it is entirely out of sight and at any distance.
My book summarized the radio-control work done at the Hammond laboratory (mostly by myself) during the period preceding that covered by the Hammond-Purington paper.1 It is curious that neither the book nor any of my subsequent publications are referenced in that paper. ….
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(2) The target-seeking feature for homing on enemy searchlights and the operative mechanism of the "electric dog" ( p. 1193) were devised and constructed under my direction while Hammond was attending the International Radiotelegraphic Conference in London in 1912.