540 lines
28 KiB
Plaintext
540 lines
28 KiB
Plaintext
Date: Sat, 16 Nov 1991 20:33:50 -0600
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From: TELECOM Moderator <telecom>
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To: telecom
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Subject: History of Morkrum Company - Ancestor of Teletype Corporation
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[Moderator's Note: Attached is a very interesting piece I received
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which is too large for a regular issue of the Digest. I thought it was
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fascinating and hope you feel the same way. PAT]
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From: Jim Haynes <haynes@cats.UCSC.EDU>
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Subject: History of Morkrum Company - Ancestor of Teletype Corporation
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Organization: University of California, Santa Cruz
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A BRIEF HISTORY OF THE MORKRUM COMPANY
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Howard L. Krum
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circa 1925
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ABSTRACT
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This is a first-hand report of Teletype's early years. Although the
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original manuscript was found unsigned and undated, it has been
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positively identified as the work of Mr. Howard L. Krum, son of Mr.
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Charles L. Krum, a co-founder of the original Morkrum Company. The
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date of writing seems to have been somewhere between 1925 and 1928.
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The fame of Howard Krum does not depend on his illustrious
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parentage. His own contributions to the printing telegraph art, among
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them the invention of _stop-start synchronization_, were of lasting
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importance.
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-----
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In the year 1902, Mr. Joy Morton, nationally known as the founder
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and head of the Morton Salt Company, became interested in the
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possibility of developing a printing telegraph system. He called Mr.
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Charles L. Krum, who was at that time Mechanical Engineer of the
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Western Cold Storage Company, into consultation on the matter. While
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cold storage seems rather a far cry from printing telegraph
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development, Mr. Krum had had considerable experience on the design of
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intricate mechanisms, including adding machines.
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Inventors had been working on the development of printing telegraph
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for forty years prior to this time but had not succeeded in producing
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apparatus which was simple and practical enough to find any market or
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any considerable use by the communication systems in the United
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States. As is the case with most others who started work on printing
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telegraph, Mr. Krum was fascinated with the possibilities of this
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development, and Mr. Morton agreed to go ahead with the proposition
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and finance it. How important this decision was did not become
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apparent for many years, as certainly no one realized the vast sums of
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money and the years of hard work which would have to be expended
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before satisfactory printing telegraph apparatus would be produced and
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widespread use made of it.
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In 1906, Mr. Howard Krum received his degree in electrical
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engineering and immediately started work with his father on this
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problem. The combination of the electrical engineer and the
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mechanical engineer proved to be a happy one and experiments were
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diligently prosecuted for a couple of years, until in 1908 a system
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was developed which looked good enough to try on an actual telegraph
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line. The first trial of this system was made on the lines of the
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Chicago & Alton Railroad. While operation was secured and the results
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were sufficiently satisfactory to cause the inventors to feel quite
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jubilant, still they were hard-headed enough to see the weak points of
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this system in the state of development in which it was at that time.
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The experience acquired in this actual line test of the apparatus was
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made the basis for further research, and after two more years of work,
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the start-stop printing telegraph system which has become the basis
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for all successful single channel printer systems of the present day,
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was born. The apparatus which embodied the start-stop system at that
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time bore little resemblance to the present apparatus but the
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principles of operation were there and the working out of them was
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sufficiently satisfactory to justify a commercial installation.
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In their pursuit of a satisfactory system of transmission, the
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mechanism for recording the signals was not neglected. Several
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different kinds of commercial typewriters were modified to perform the
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duty of recording the received signals, but strange as it may seem, it
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was found that commercial typewriters were not satisfactory for the
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rigorous job of recording telegraph signals. It was therefore found
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necessary to design a typewriter especially for this work.
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These first tests also pointed out the advantages and superiority of
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mechanical over electrical operation, with a result that all functions
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outside of the bare selection are now performed mechanically by the
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Teletype in its present form.
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Having finally produced a system and apparatus which they felt
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certain was commercially practical, the inventors were then faced with
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the necessity for finding a communication company who would permit the
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installation of this apparatus in regular commercial operation. The
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Postal Telegraph Company proved to be the most receptive and a commit-
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tee headed by Mr. Minor M. Davis, at that time Electrical Engineer for
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the Postal Telegraph Company, visited Chicago to investigate this new
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Morkrum system. It is interesting to note that Mr. Davis, who had
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years of experience in the telegraph business and who had seen many
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attempts at the development of a successful printing telegraph system,
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was not so much concerned in the actual functioning of the recording
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apparatus but was more concerned in learning if the basis of the
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system, that is, the line signal, was of a type which would function
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on ordinary telegraph lines in good weather and bad. After a thorough
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investigation of the system, he became convinced that the start-stop
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line signal devised by the Krums would meet the rigorous service
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requirements, and the committee decided to permit an actual commercial
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installation on the Postal lines between New York and Boston. This
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installation was made in the summer of 1910.
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After years of work, the inventors felt that they had finally
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reached their goal. The apparatus was packed and shipped and Mr.
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Howard Krum went to Boston to supervise the installation at that end
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of the circuit and Mr. Charles Krum went to New York to take care of
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the operations at that end. However, the difficulties were not yet
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over, for when the apparatus arrived at its destination it was found
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that due to rough handling the delicate instruments were so badly
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damaged that instead of proceeding with the installation they had to
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spend months of work to get the machines back in shape for operation.
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Finally the day came when everything was in readiness and the two
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sets, one at New York and one at Boston, were hooked together by a
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telegraph wire and the first commercial message was transmitted by the
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Morkrum system.
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From the start good results were obtained, but as operation
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continued the inventors realized more and more that the operating
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requirements for commercial telegraph service were terribly exacting.
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The percentage of accuracy required was much higher than with any
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other form of mechanism; it must work twenty-four hours a day; it must
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operate on good telegraph wires and on telegraph wires whose quality
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was impaired by rain and other adverse weather conditions. The
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apparatus was too delicate to function over long periods of time
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without the necessity of close supervision. However, as in the case
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of the earlier installation, the inventors profited by their
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experience and went steadily along perfecting their apparatus, making
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changes here and there to improve its accuracy [and] to make it
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sturdier and simpler. Further Postal Telegraph lines were equipped
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and an installation was made on the Chicago, Burlington & Quincy
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Railroad between Chicago and Galesburg, Illinois.
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However, in spite of the fact that these circuits gave good service,
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the growth of the business was very slow. Telegraph companies and the
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railroads seemed loath to adopt the new system. Possibly this slow
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growth in the early days of the Morkrum system was due to the fact
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that the telegraph companies and the railroads could easily secure
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good Morse operators at low wages. Therefore, they were loath to
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abandon Morse operation, concerning which they were thoroughly
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familiar, and to replace it with machine telegraphy which would force
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them to go to school all over again.
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However, the telegraph business continued to grow and good Morse
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operators became harder to secure, wages increased, and above all, the
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Morkrum system steadily improved and finally installations of the
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system were made by the Western Union Telegraph Company, and the
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Canadian Pacific and Great Northwestern Telegraph companies in Canada.
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Due to increased business, Morkrum Company were able to enlarge
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their plant facilities, to engage expert assistants and to steadily
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improve their product.
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In 1917, Mr. Sterling Morton, son of Mr. Joy Morton, who had had
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wide experience with the Morton Salt Company, became president of the
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Morkrum Company. Mr. Morton brought to the Morkrum Company not only
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his great organizing and executive ability, but also an unusual talent
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for machine design work. The page printer and the Simplex tape
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printer, which are the most widely used units at the present time, are
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the joint work of Mr. Morton and Mr. Howard Krum.
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Up to this time, the laboratory and manufacturing work had been
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carried on in an old building near the business district. A careful
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survey of the employees showed that the majority of them lived on the
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north side of Chicago and this study determined the location of the
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present factory. In 1918, the factory was moved to the first unit of
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the present building, which is entirely fireproof and is considered
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one of the finest factory buildings in Chicago. Since that time, a
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total of six units have been built and a seventh is just being
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started. [1]
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As the demand for printing telegraph apparatus grew, the standards
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were steadily raised and apparatus which was thought quite wonderful a
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few years previous became obsolete and was replaced with newer types
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having greater margins of operation, higher speeds, and which were
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much simpler to maintain. Installations were made in new fields and
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each new field offered new and more difficult problems.
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In 1914, Mr. Kent Cooper, who was then head of the Traffic
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Department of the Associated Press, became convinced that the method
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of delivering copy to the New York newspapers by messenger boy was
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decidedly unsatisfactory and asked the Morkrum Company if they could
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make an installation of their apparatus by which one operator in the
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Associated Press could transmit the press matter simultaneously to all
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of the newspapers in New York City. A simple problem in the light of
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our present-day knowledge, but at that time it was an undertaking
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which offered many problems as yet unsolved. However, it was
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undertaken; the problem was studied, suitable apparatus was designed
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and within a year all of the newspapers in New York City and nearby
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towns, as well as in Philadelphia, were receiving their press matter
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simultaneously from a transmitting set controlled by a single operator
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in the Associated Press office in New York City.
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From this small beginning in the service of the Associated Press, the
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use of printing telegraphs has spread until over 800 newspapers
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belonging to the Associated Press receive their news dispatches by
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these machines, and some of the wire circuits of which this matter is
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transmitted involve as much as 4,000 miles of wire. The other press
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associations are using the apparatus to much the same extent.
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Up to 1917, the Morkrum Company had devoted all their efforts to the
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design of single channel printing telegraph systems and had developed
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both direct keyboard and tape transmission, but at this time the
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Postal Telegraph Company asked the Morkrum Company to develop a
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Multiplex system to meet the requirements on their heavy trunk lines.
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This development was undertaken and in less than a year a satisfactory
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Multiplex system had been designed, manufactured and installed on the
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Postal Company's line and proved so valuable that its use was extended
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to all their main trunk lines.
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As the use of printing telegraph became more general, needs
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developed for different types of apparatus to meet different classes
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of service, and the Morkrum Company attacked these problems and devel-
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oped different types of apparatus until at present there are available
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both direct keyboard and perforated tape transmission systems,
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printing either on tape printers or page printers, operated either
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single channel or Multiplex, using either five-unit or six-unit code,
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the latter being especially valuable for stock quotation work.
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The use of the apparatus in the telegraph companies continued to
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grow until at the present time fully 80% of all commercial telegrams
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are handled by printing telegraph. As the use of the machines grew,
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the requirements became more and more rigid and these were met by
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intensive research and development work which has never ceased.
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Printers are operating today under service conditions which would not
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have been considered possible even two or three years back. The
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latest development, the so-called "Typebar Tape Teletype" has proven
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so simple and reliable that it bids fair to drive Morse operation even
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from the way wires.
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Always on the alert for new fields for its equipment, the Morkrum
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Company several years ago became convinced that its apparatus could
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render valuable service for the communication needs of business
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houses, factories, hotels, etc. To sell this idea required a lot of
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time and much hard work, and the first few installations proved that
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this service was much more exacting that the use of the machines in
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regular telegraph offices where expert maintenance was instantly
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available, The experience gained in these early commercial install-
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ations paid big dividends, in that it resulted in such marked
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improvement in the apparatus that the use has grown so that today
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there is scarcely a city or town in the United States where this
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apparatus is not used for some communication need outside of its
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primary field -- that of telegraphic message traffic.
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The development of an organization that could satisfactorily handle
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the complex problems of developing and manufacturing a printing
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telegraph system has been quite as remarkable as the development of
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the apparatus itself; in fact, the successful culmination of the work
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would not have been possible had it not been for the splendid loyalty
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and intelligent work of the whole organization. This is particularly
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true in the case of the many men who had courage enough to stick to
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the proposition through the many years that it took before practical
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commercial results were obtained. The Morkrum Company is particularly
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proud of the fact that the outstanding men in the organization have
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developed in their own organization. It is a fixed policy of the
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company to develop its own men for important positions wherever
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possible.
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Mr. Howard Krum met Mr. J. O. Carr, who is now head of the Sales
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Engineering Department, in Boston in 1910 and engaged him for testing
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and engineering work. About the same time, Mr. G. Heding, who is now
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Factory Manager, came to the company as a tool maker. During their
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long years of service these two men have filled practically every
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position of importance in the organization and much credit is due them
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for their part in the final success of the work. We believe there are
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few companies where such a large proportion of the men in supervisory
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positions have grown up with the company and developed as the company
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has developed and there are certainly few companies where there is a
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greater spirit of loyalty and co-operation.
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Just a word about the manufacture of this apparatus. The requirements
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which printing telegraph apparatus must meet are extremely severe.
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This is readily understood when it seen that when a printer is opera-
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ting at the rate of 60 words per minute it is printing six characters
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per second. The printing of a character requires at least four
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successive operations of the various portions of the machine; in other
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words, many of these mechanisms have less than a twenty-fourth of a
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second in which to do their job. Coupled with this is the fact that
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the control of this rapidly moving mechanism is by means of a current
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of electricity so weak that it would hardly cause the smallest
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electric light globe to even glow.
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Knowing this, it is easy to understand that continuous work and
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research must be carried on to secure proper alloys and devise the
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proper methods of heat treating and hardening to permit all of the
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parts of the machine to function properly.
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Another requirement which is successfully met by Morkrum apparatus
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is absolute interchangeability of parts. This has been secured by the
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work of a force of highly trained designers and engineers and by the
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policy of the company of unhesitatingly securing the finest machine
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tool equipment available to permit parts to be made with the highest
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degree of accuracy. The present plant of the Morkrum-Kleinschmidt
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Corporation [2] at Chicago contains about 135,000 square feet of floor
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space devoted solely to the manufacture of this type of apparatus,
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filled wit the best machine tool equipment that can be purchased and
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manned by a force of highly trained employees, many of whom have been
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in the service of the company for a great many years.
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-----
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[1] This would be the building at 1400 Wrightwood Ave., in Chicago
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which was occupied by Teletype until early in the 1960s, when the R&D
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portion of the complex at 5555 Touhy Ave., Skokie, was completed. I
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hear it has now been remodeled into luxury apartments.
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[2] E. E. Kleinschmidt had a competing printing telegraph company in
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the 1905-1920 time frame. His company eventually merged with the
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Morkrum company because of the dominance of the Krum patent on
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start-stop operation. In the 1950s Mr. Kleinschmidt got back into the
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business with his own company, located in Deerfield, IL.
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haynes@cats.ucsc.edu
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haynes@ucsccats.bitnet
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------------------
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From: Jim Haynes <haynes@cats.UCSC.EDU>
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Subject: History of Teletypewriter Development
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Date: 17 Nov 91 08:34:46 GMT
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Organization: University of California, Santa Cruz
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Here's another one (and that exhausts my supply). These two came into
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my hands as Monographs when I was working for Teletype in 1963-1966.
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The main reason I typed them in is to get them into the telecom
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archive since they contain information that isn't readily available so
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far as I know.
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HISTORY OF TELETYPEWRITER DEVELOPMENT
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R. A. Nelson
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K. M. Lovitt, Editor
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October 1963 Teletype Corporation
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5555 West Touhy Avenue
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Skokie, Illinois
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------
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ABSTRACT
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The success of the modern teletypewriter began with Howard L. Krum's
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conception of the start-stop method of synchronization for permutation
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code telegraph systems. The purpose of this paper is to provide a
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brief historical account of events which led to that achievement and
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of those which ensued.
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Four areas of development will be covered:
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(1) The contributions of Sterling Morton, Charles L. Krum and
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Howard L. Krum.
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(2) The contributions of E. E. Kleinschmidt.
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(3) The contributions of AT&T and Western Electric.
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(4) The contributions of L. M. Potts
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-----
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_HISTORY OF TELETYPEWRITER DEVELOPMENT_
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Area I. In 1902 a young electrical engineer named Frank Pearne
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solicited financial support from Joy Morton, head of the Morton Salt
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interests. Pearne had been experimenting with a printing telegraph
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system and needed sponsorship to continue his work. Morton discussed
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the matter with his friend, Charles L. Krum, a distinguished
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mechanical engineer and vice president of the Western Cold Storage
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Company (which was operated by Joy's brother, Mark Morton). The
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verdict for Pearne was favorable, and he was given laboratory space in
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the attic of the Western Cold Storage Company.
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After about a year of unsuccessful experimenting, Pearne lost
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interest and decided to enter the teaching field. Charles Krum
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continued the work and by 1906 had developed a promising model. In
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that year his son, Howard, a newly graduated electrical engineer,
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plunged into the work alongside his father. The fruit of these early
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efforts was a typebar page printer (Patent No. 888,335; filed August
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22, 1903; issued May 19, 1908) and a typewheel printing telegraph
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machine (Patent No. 862,402; filed August 6, 1904; issued August 6,
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1907). Neither of these machines used a permutation code.
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They experimented with transmitters as well, applications filed in
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1904 and 1906 maturing into Patents No. 929,602 and No. 929,603.
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These patents covered modes of transmission which depended both on
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alternation of polarity and change in current level.
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By 1908 the Krums were able to test an experimental printer on an
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actual telegraph line. The typing portion of this machine was a
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modified Oliver typewriter mounted on a desk with the necessary
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relays, contacts, magnets, and interconnecting wires (Patent No.
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1,137,146; filed February 4, 1909; issued April 27, 1915). As a result
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of the successful test of this printer, Charles and Howard Krum
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continued their experiments with a view to developing a direct
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keyboard typewheel printer.
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They sought most of all to discover a way of synchronizing
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transmitting and receiving units so that they would stay "in step."
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It was Howard Krum who worked out the start-stop method of
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synchronization (Patent No. 1,286,351; filed May 31, 1910; issued
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December 3, 1918). This achievement, which more than anything else
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put printing telegraphy on a practical basis, was first embodied (for
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commercial purposes) in the "Green Code" Printer, a typewheel page
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printer (Patent No. 1,232,045; filed November 28, 1909;issued July 3,
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1917).
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The transmitters first used by the Krums were of the continuously-
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moving-tape variety. (A stepped tape feed, they maintained, would have
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reduced transmission speed.) In order to permit sequential sensing,
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the rows of code holes were arranged in a slightly oblique pattern
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(with respect to tape edges). This method of transmission is more
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fully elaborated in Krum Patents No. 1,326,456, No. 1,360,231, and No.
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1,366,812.
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Keyboard-controlled cam-type start-stop permutation code transmitters
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were developed by Charles and Howard Krum in about 1919. Such a
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device is the transmitter component of the Morkrum 11-Type tape printer
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(Krum Patent No. 1,635,486). This kind of transmitter employs a
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single contact to open or close the signal line.
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In about 1924 the Morkrum Company introduced the No. 12-Type tape
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printer (H. L. Krum Patent No. 1,665,594). On December 23, 1924,
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Howard Krum and Sterling Morton (son of Joy Morton) filed an
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application on the 14-Type type-bar tape printer which matured into
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Patent No. 1,745,633. [1]
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Area II. It appears that the early efforts of E. E. Kleinschmidt
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were directed toward development of facsimile printing apparatus and
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automatic Morse code equipment. He patented first a Morse keyboard
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transmitter (Patent No. 964,372; filed February 7, 1095; issued
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January 11, 1910) and later a Morse keyboard perforator (Patents No.
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1,045,855, No. 1,085,984, and No. 1,085,985). (The latter became
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known as the Wheatstone Perforator.)
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In 1916 Kleinschmidt filed an application for a type-bar page
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printer (Patent No. 1,448,750 issued March 20, 1923). This printer
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utilized Baudot code but was not start-stop. It was intended for use
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on multiplex circuits, and its printing was controlled from a local
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segment on a receiving distributor of the sunflower type. Later,
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around 1919, Kleinschmidt appeared to be concerned chiefly with
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development of multiplex transmitters for use with this printer
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(Kleinschmidt Patent No. 1,460,357).
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It seems that Kleinschmidt first became interested in modern
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start-stop permutation code telegraph systems when H. L. Krum's basic
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start-stop patent was issued in December 1918. Shortly after that
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Kleinschmidt filed an application entitled "Method of and Apparatus
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for Operating Printing Telegraphs" (Patent No. 1,463,136; filed May 1,
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1919; issued July 24, 1923). The system described therein employed
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the start-stop principle with a modified version of his earlier
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multiplex distributor. That patent, accordingly, was dominated by the
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Krum start-stop patent. The conflict of patent rights between the
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Morkrum Company and the Kleinschmidt Electric Company eventually led
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to a merger of the two interests.
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Shortly after the new Morkrum-Kleinschmidt Corporation (later called
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the Teletype Corporation) had been established, Sterling Morton,
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Howard Krum, and E. E. Kleinschmidt filed an application covering the
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commercial form of the well-known 15-Type page printer (Patent No.
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1,9904,164). [2]
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Area III. Teletype entered the Bell System in 1930. From this
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point on, advances in the Teletype product can be considered the
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result of the pooled efforts of the AT&T Company, the Western Electric
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Company, and the Teletype Corporation. Teletype Corporation, of
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course, holder of the basic patents and expert in the art, was the
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chief contributor.
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Although it appears from the report of R. E. Pierce, dated December
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24, 1934, that the Bell System was active in the development of
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telegraph printers and transmitters as early as the year 1909, a
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review of the patents issued to Bell reveals no significant
|
|
contribution to modern teletypewriter development (using start-stop
|
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permutation code) until the introduction in 1920 of the 10-A
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teletypewriter (Pfannenstiehl Patents No. 1,374,606, No. 1,399,933,
|
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No. 1,426,768, No. 1,623,809, and No. 1,661,012).
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The 10-A teletypewriter was the first embodiment of such basic
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|
design features of the 15-Type printer as stationary platen, moving
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|
type basket, and selector vane assembly, but the majority of
|
|
improvements incorporated in the 15-Type were proprietary to the
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|
Teletype Corporation.
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Area IV. The earliest contribution of Dr. L. M. Potts to the
|
|
start-stop method of synchronization appears to have been set forth in
|
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a patent application filed November 18, 1911, covering a reed-type
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start-stop selector (Patent No. 1,151,216).
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In 1914, Dr. Potts filed an application for a single magnet page
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printer which used an eight-unit code (Patent No. 1,229,202; issued
|
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June 5, 1917).
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In 1915, Dr. Potts filed an application covering another single
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magnet page printer, this one using the start-stop permutation code
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(Patent No. 1,370,669; assigned to AT&T March 8, 1921).
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Potts Patents No. 1,517,381 and No. 1,570,923 were also assigned to
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AT&T.
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----------
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[1] For anyone who is old enough to have seen a Western Union Telegram
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where the typing is on narrow gum-backed tape that is moistened and
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stuck to a telegram blank, this is the machine that produces that kind
|
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of printing. The same mechanism is the basis of a typing reperforator,
|
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a machine which punches received signals into a tape for retransmission
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and also types on the tape so an operator can read it.
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[2] This is the machine used until the 1960s or so by the news wire
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services. Some radio stations still use a recording of the sound of
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one of these machines as background during news broadcasts.
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haynes@cats.ucsc.edu haynes@cats.bitnet
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[Moderator's Note: Thank you for two very excellent articles this
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weekend on the history of Teletype and its predecessor companies.
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Jim's earlier article on the history of the Morkrum Company was
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distributed as a special mailing sent out between issues 936-937 on
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Saturday evening. Watch for your copy to arrive if it hasn't yet.
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But I am curious about something not mentioned in either article. Did
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the Bell System buy out Morkrum and change the name to Teletype in
|
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1930 or did Teletype start and later buy out Morkrum? How did that
|
|
transition occur? I love these history articles because so much
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telecom history happened right here in Chicago -- the Chicago I like
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to remember from years ago. PAT]
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