by Seth Shulman
For reasons that have never been fully explained, Brown never did succeed in filing Bell’s patents in England. Nonetheless, given the omission of any mention of variable resistance in Brown’s copy of Bell’s patent application, the conclusion is almost inescapable: it was missing from the version Bell handed him on January 25. Even the historian Robert Bruce, who so regularly gives Bell the benefit of the doubt in such matters of controversy, finds the omissions in the Brown patent version irregular. As he writes,
Whatever the reason, the fact that the George Brown specification did not mention even the principle of variable resistance suggests that the whole idea had also been left out of the American specification draft as it stood early in January 1876.
Of course, given the fact that the Brown meeting took place on January 25, Bruce would have been more accurate to say that the incident suggests the idea of variable resistance had been left out up until that time. Unless Bell somehow mistakenly gave Brown an earlier, incomplete version of his application (unlikely, given Bell’s diligent preparation throughout the month of January), the concept of variable resistance was simply not part of Bell’s patent application at that time. If the addition had not been made by January 25, the fact casts considerable doubt on Bell’s story that he added this information on the night of January 12 in a bout of inspiration “at the last moment.” In other words, the language about variable resistance was most likely also absent from the version of his patent application that Bell swore to before a notary public on January 20—the version that was then purportedly held by Pollok & Bailey to ultimately be filed at the Patent Office on February 14.
IN THE COURSE of my efforts to get to the bottom of the variable resistance tangle, I happened across the fascinating work of a retired patent attorney named Burton Baker. Baker first became interested in Elisha Gray’s story in 1958, while working as a patent lawyer for the Whirlpool Corporation in Michigan. At the time, the head of Whirlpool was none other than Elisha Gray II, the inventor’s grandson. Upon his retirement, Baker decided to investigate the story of the patenting of the telephone in earnest, focusing on the mystery surrounding the origin of the variable resistance passage in Bell’s patent application.
Baker went to great lengths to track down the story, finding no fewer than six versions of Bell’s patent, including a copy of his application kept at the National Archives in Washington, D.C.; his “file copy” at the Library of Congress; and another, lesser-known copy held at the New England regional office of the National Archives in Waltham, Massachusetts. He studied everything from the handwriting on each to the type of paper the originals were written on, and he cataloged the differences among all the extant versions. Eventually, he compiled these and other findings in an interesting self-published book called The Gray Matter: The Forgotten Story of the Telephone.
I tracked Baker down by phone at his home in Michigan, and we compared notes at some length about the history of the telephone. Baker said that his close look at Bell’s patent applications convinced him that Bell penciled in the additional information about variable resistance only after his patent application had been filed—and after he had seen Gray’s caveat. As Baker states in his book:
It is my firm conclusion that Bell learned enough of the contents of the Gray caveat, then added the word description of a liquid transmitter to his 10-page “file copy” of the application.
As Baker sees it, Bell’s additions must have then somehow been handed to a copyist to prepare a new version that seamlessly included the additional information. The timing Baker proposes makes the prospect difficult to imagine because it means changes must have been made and recopied sometime after Bell’s arrival in Washington on February 26 and yet before Wilber sent the patent to be formally printed on March 3. If Baker is right, though, Bell’s central claim to variable resistance—so central to the technological and legal success of the telephone—becomes little more than a fraud.
Baker’s theory involves a bit of informed speculation. What is indisputably clear, however, is that more than just the timing is awry in the fundamental mystery surrounding Bell’s inclusion of the concept of variable resistance in his patent application. Bell’s version of events brims with troubling inconsistencies, coincidences, and irregularities. If Bell is telling the truth, what evidence is there that he had previously considered the possibility of using variable resistance to transmit speech?
Dealing with this issue in court, Bell’s legal team relied heavily upon a letter Bell wrote to Gardiner Hubbard on May 4, 1875. In it, Bell makes reference to the concept of variable resistance:
I have read somewhere that the resistance offered by a wire…is affected by the tension of the wire. If this is so, a continuous current of electricity passed through a vibrating wire should meet with a varying resistance, and hence a pulsatory action should be induced in the current.
The letter shows that Bell possessed some basic understanding that varying the resistance of an electrical circuit could be a useful concept for his research. As he explains to Hubbard, he actually did try an abortive experiment to test this notion, using the piano of his neighbor, Don Manuel Fenollosa. But, according to Bell, the experiment failed, presumably because the piano strings were all essentially attached to one another on its metal frame, obscuring the effect. And, by Bell’s own account, he never tried any other means to reduce this concept to practice prior to his telephone patent application. The key point, of course, is that the concept Bell outlines in his May 4 letter, while important, is a far cry from a workable scheme like Gray’s liquid transmitter design. And Bell doesn’t pursue this approach until it mysteriously turns up in the margins of his patent application some eight months later.
Even if Bell had considered the idea of variable resistance at this earlier point in his research, it is still reasonable to wonder what made him think to add it at the last minute to his patent application. Responding to a question about the matter in court many years after the fact, Bell for the first time volunteered an additional explanation. He said that in January 1876, when he was completing his telephone patent, he was also preparing to apply for a patent on his invention of a so-called spark arrester, a device designed to prevent sparks jumping from the connections of electrical devices like telegraphs with intermittent connections.
According to Bell, at the last moment before sending his telephone patent to Pollok & Bailey, he remembered his idea for the spark arrester, which involved submerging the electrical leads in water. He said the notion gave him the idea of using a liquid to vary the resistance in a circuit as a way to transmit sound. Oddly, though, in his last-minute addition, Bell didn’t offer the example of using water the way he had proposed to do in the spark arrester. Instead, his patent suggests the use of mercury. As noted above, the language in the patent proposes:
For instance, let mercury or some other liquid form part of a voltaic circuit, the more deeply the conducting wire is immersed in the mercury or other liquid, the less resistance does the liquid offer to the passage of the current [emphasis added].
If Bell was, as he attests, reminded of his water-based invention of the spark arrester, why would he suggest the use of mercury? One would imagine that Bell would have known that mercury’s low resistance makes it particularly ill suited to the task he had in mind. Could it be that Bell, or whoever hastily inserted this addition to his patent, merely wanted to use an example that didn’t seem so obviously cribbed from Gray’s design?
Bell’s explanation is instructive. He testifies that
This application of the spark-arrester principle to the mode of producing electrical undulations by varying the resistance of the circuit occurred to me, as I have already said, while I was making the final revision of my specification for the United States Patent Office, and almost at the last moment before sending it off to Washington to be engrossed…. When I came to describe the proposed mode of affecting the external resistance by the vibration of the conducting wire in water, it occurre
d to me that water was not a good illustrative substance to be specified in this connection, on account of decomposability by the action of the current. I therefore preferred to use as a typical example a liquid that could not be decomposed by the current, and specified mercury as the best example of such a liquid known to me.
Of course, the vagueness of Bell’s description of his variable resistance scheme involving a wire vibrating in mercury would likely have been less of a significant issue in court had the Patent Office, following its normal procedure, required Bell to submit a working model of his invention. I learned, however, that Wilber, responding to Bell’s clever emphasis on his claimed invention of the “undulatory current” that made electrical transmission of sound possible, had exercised his discretion as a patent examiner in the matter, making an official notation on the file wrapper of Bell’s application that no drawing or model would be necessary in Bell’s case. We may never know what motivated Wilber to waive the model requirement, but the mere fact that he did so cleared up a question that had been nagging at me from the start.
Despite all the reams of testimony, it remains profoundly unclear when Bell actually inserted the language of variable resistance into his patent. It could have occurred at Pollok & Bailey’s office prior to the application’s submission on February 14, but after Pollok, Bailey, and/or Hubbard were somehow tipped off about the imminent filing of Gray’s caveat. Given the tight-knit and closely connected world in which Pollok and Bailey operated, such a tip-off is very easy to imagine. A relatively small group of patent lawyers interacted regularly with the Patent Office examiners. Many of the top legal offices, including that of Pollok & Bailey, were just doors away from the handsome Patent Office building near the Capitol. A small network of regular inventors, draftsmen, and copyists all worked closely with one another and no doubt socialized, making the exchange of information about the latest new invention commonplace.
It is even possible to imagine, given the circumstances involved, that Bell himself did not make, authorize, or even know about the addition, just as he claims not to have known about Hubbard’s abrupt decision to file that day. Whatever information Hubbard, Pollok, Bailey, or someone else from their office could have had about Gray’s imminent filing might have been hastily used to add language to defend Bell’s claim against Gray’s caveat. In such a scenario, Bell might have later put the additions in the margins of his own file copy to make it fully comport with the one that had been filed.
Information about variable resistance could also have been added after Bell’s meeting with Wilber in Washington. Wilber does not confess to having allowed such a change; however, he does comment that security at the Patent Office was lax, and it would certainly have been possible, given Pollok and Bailey’s connections, for someone to have removed Bell’s patent and made changes to it after hours.
However it might have happened, though, the facts of the case strongly suggest that the addition of the concept of variable resistance to Bell’s patent was made after the rest of his application had been completed. Furthermore, the text Bell inserted into his patent bears such a striking resemblance to Gray’s description in his caveat that it cannot be easily explained away. A final inconsistency to consider is this: If, as Bell says, Wilber’s only hint about Gray’s work came by pointing to the paragraph inserted in Bell’s application concerning the use of “mercury or some other liquid” to vary resistance, why would Bell write to Gray in 1877 that he had heard that Gray’s caveat concerned a wire “vibrating in water”?
Amazingly enough, in the voluminous Bell archive, even this question was directed to Bell in one of the many court cases in which he testified. As the opposing counsel asked Bell:
How did you come to know that Elisha Gray’s caveat “had something to do with the vibration of a wire in water” and just what was the full extent of your information on the subject, up to the date of your said letter of March 2, 1877?
In response, Bell seems to be uncharacteristically at a loss for an explanation:
I do not know what it was that led me to imagine that the caveat had something to do with the vibration of a wire in water, unless, indeed, it might have been due to the fact that the liquid I had in contemplation when I first wrote the paragraph from my specification quoted above, was water, and not mercury, as stated in that paragraph; and to the fact that I had previously experimented with water in my spark arrester.
Among the many close observers of the Bell saga to note the flimsiness of this explanation is Lloyd Taylor. As he aptly puts it,
On this gossamer thread, spun four years after the event, hangs Bell’s sole claim to priority in the concept of the liquid transmitter.
14
CALL WAITING
I HAD UNEARTHED enough information so far to raise serious doubts about Bell as the sole inventor of the telephone. And yet, over a century later, this is largely how he is remembered. The image of Bell as the smiling, portly, white-haired “father of the telephone” lives on today in science textbooks, children’s stories, and scholarly works alike. I was not entirely sure how the myth of Bell’s single-handed invention of the telephone managed to survive unscathed in his own time in the face of the incriminating evidence against him that emerged in court—from the irregularities at the U.S. Patent Office to the suspiciously missing paragraph about variable resistance in the version of his patent application Bell sent to England. But I was even more mystified by the way Bell’s stature in the public imagination could have proved so unshakable given a steady onslaught of efforts by assorted researchers, including Silvanus Thompson, Lloyd Taylor, Burton Baker, A. Edward Evenson, and many others, over the course of more than a century to correct the record.
Clearly, one explanation is that history’s winners stand in the best position to control the way events are remembered. And the Bell Telephone Company, which began to amass immense profits from its monopoly position as the 1800s wore on, was certainly a winner. For a dramatic example of this phenomenon at work in the case of the telephone, consider the case of George Prescott.
In 1878, Prescott published a book entitled The Speaking Telephone, Talking Phonograph and Other Novelties. Prescott was a respected electrical researcher and author and a contemporary of Gray and Bell. In 1878, he served as Western Union’s chief engineer, which meant that he would have likely tended to ally himself more closely with Gray’s work than Bell’s. By then, Gray was working as an independent inventor, but he still licensed many of his inventions to Western Union and its subsidiary Western Electric. Despite Prescott’s corporate affiliation, though, he was also a prolific writer with a reputation for fairness and independence in his work. He was also certainly one of the most knowledgeable individuals of his day to report on the developments surrounding the introduction of the telephone.
In the first edition of Prescott’s book, written two years after Bell received his patent on the telephone, Prescott explicitly credits Gray with the invention. After reviewing the features of all the brand-new telephone models of his day, including Bell’s, he notes that
all the Speaking Telephones which we have described possess certain common characteristics embodied in Mr. Gray’s original discovery, and are essentially the same in principle although differing somewhat in matters of detail.
As it turns out, Prescott’s first edition is now exceedingly rare. When Western Union settled its Dowd lawsuit with the Bell Telephone Company in November 1879, the terms of the settlement dictated that Western Union had to unequivocally acknowledge Bell as the inventor of the telephone. Prescott, given his affiliation with Western Union, may have felt obligated to accede to the demand. One way or the other, however, the history of the telephone presented in his book was thoroughly rewritten in the subsequent 1884 edition. Consider the passage cited above, for instance. It was changed to read as follows:
all the Speaking Telephones which we have described possess certain common characteristics embodied in Mr. Bell’s original discovery, and are ess
entially the same in principle although differing somewhat in matters of detail [emphasis added].
Perhaps an even more revealing change was made to Prescott’s particular discussion of the liquid transmitter. In his first edition, Prescott presents a diagram of the liquid transmitter (labeled fig. 52) accompanied by the following note at the bottom of the page:
From the reading of the text it might be erroneously inferred that the apparatus shown in figure 52 was invented by Professor Bell, and exhibited by him at the Centennial Exhibition. Professor Bell neither invented nor exhibited it. The above figure represents the transmitting portion of Elisha Gray’s original Speaking Telephone—the first articulating telephone ever invented.
Prescott’s analysis in his first edition could hardly be more explicit. But, of course, this informative note is omitted entirely in subsequent editions. Fittingly, even the title of his book was changed. From 1884 on, it was published as Bell’s Electric Speaking Telephone: Its Invention, Construction, Application, Modification and History. Equally important, this whitewashed version of Prescott’s initial work would become a significant and widely read text, published most recently in a 1972 reprint by a former publishing subsidiary of the New York Times. As the saying goes, to the victor go the spoils.
Prescott’s case, fully exposed by previous writers of telephone history including Lloyd Taylor and A. Edward Evenson, is of course an extreme case. To be sure, many more subtle pressures must be at work to explain why certain kinds of erroneous historical myths seem to stubbornly survive all efforts to amend them.
