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THEILER Telephones

by Ric Havyatt

Telephones manufactured by Meinrad Theiler and Sons have been briefly described in previous issues of ATCS Newsletters (May 1992 and September 1995). Although of Swiss-German origin, the firm operated as instrument makers at 64 Canonbury Road, North London not far from ‘The Angel Islington’ of Monopoly fame. They were at this address 1881-1882 and during this period became involved with the manufacture of telephones of both the magneto public service and battery operated intercom types. In 1883 they returned to Switzerland, to the town of Einsiedeln and then to the town of Schwyz 1885 to 1903.

Their telephones came to Australia in 1882 as a result of a contract placed by the NSW Electric Telegraph Department for instruments from a number of manufacturers to be evaluated for the fledgling telephone service in NSW.

The telephone described in the ATCS May 1992 article was a friction-drive magneto wall instrument for use in the public telephone system whilst the September 1995 article described an intercom instrument. (Click here to view this site.) In both examples, however, the receivers were missing and at the time nobody could come up with any suggestions as to the form that these receivers took. Just recently in Melbourne, Linley Wilson located some ‘spoon’ type receivers. By a lucky chance some information was obtained from a Swiss museum publication which included illustrations of a Theiler intercom phone with receiver attached. Also illustrated separately was a Theiler receiver of the earlier type with the external ring magnet, being the same as those shown on the intercom phone.

Three forms of receiver have now been identified and these are shown in the drawings. They all have similar dimensions but vary in construction material and the means by which the receivers were polarised.

The earliest construction was a double pole unit having a circular shaped magnet attached to the back of the case. The body of the receiver was wood with a wood earcap and wood handle. The backplate was brass, suitably lacquered.

The method of construction was then changed to have all three pieces of the receiver shell and the handle formed from ebonite, but still retaining the circular polarising magnet attached to the back of the receiver case.

The final form, as far as present knowledge allows, was for the magnet to incorporated inside the receiver shell and to have only a single pole piece and coil. Again, the material for all structural components was ebonite.

We are indebted to Linley for his identification of the correct receiver for these phones and indirectly to G A Kopsch, Chief Mechanician of the NSW Electric Telegraph Department in the1880s. Mr Kopsch kept records of the various instruments and components used in NSW at that time and also kept examples of much of this equipment. It is from the Telecom Display Collection in Ashfield, NSW, that the earliest Theiler wood receivers have been located, being part of the G A Kopsch collection.

Other significant items from this collection are the two instruments made by Kopsch and used in the 1877 successful telephony experiment between Sydney and Maitland spanning 140 miles. E C Cracknell, Superintendent of Electric Telephones was at the Maitland end and G A Kopsch was at the Sydney end. ATCS has been involved with the repair of one of these instruments after the ravages of borers and also in the construction of a suitable glass cabinet in which the instruments are now on display.

The discovery of the correct receivers for the Theiler phones does not unfortunately complete the investigation into these instruments. Transmitters for these phones were of the carbon pencil type and at least one transmitter diaphragm has been located in original condition but details of the bridging pencils have yet to be uncovered. The one intact diaphragm has two vertical carbons attached to the diaphragm and spaced about 20mm. Each of these has a wire to connect it back to the coil and switching circuitry. To complete the transmitter there would have been one or more bridging carbon pencils loosely resting against the vertical carbons. There is no indication whatsoever in the public system instrument of how these pencils were held in place nor is there any trace of a fitting which might have been used for this purpose. So this last remaining unknown is yet to be resolved and any assistance would be greatly appreciated.

Addendum: Since the above was written details have come to light on the device used for bridging the two vertical carbon rods glued to the diaphragm, so making a complete carbon pencil microphone. It comprises a piece of 5/16" square brass rod about 1 3/16" long having a half round carbon glued to one face. It is suspended by a string through holes at each end of the rod and hung more or less like a picture frame, being hung from the top screw of the four screws holding the diaphragm in place. It thus rests gently against the two vertical carbons to form the bridging arrangement necessary for satisfactory operation of this type of microphone. However, in light of microphone development in other areas at the time, this carbon pencil microphone would have been considered too primitive for regular use in the public telephone system, and was probably one reason for rejection of this phone.



The following added 14th November 2004 - written by Victorian collector, the late Linley Wilson.....

NOTE: THIS INFORMATION REFERS TO OTHER DOCUMENTATION, PHOTOS ETC. IN THE SUPPLEMENTARY FILE FOR THIS TELEPHONE

Theiler Telephone

Summary of Information researched by Linley Wilson (Australian Historic Telephone Society), written March 2004.

Caveat: All of this information is current and accurate to the best of my knowledge as of March 2004. Primary and/or secondary sources are quoted where available; other information deduced or of uncertain origin is annotated accordingly.

Overview:
Theiler: 'Although of Swiss-German origin, the firm operated as instrument makers at 64 Canonbury Road, North London, not far from 'The Angel Islington' of Monopoly fame. They were at this address 1881-1882 and during this period became involved with the manufacture of telephones of both the magneto public service and battery operated intercom types. In 1883 they returned to Switzerland, to the town of Einsiedeln and then to the town of Schyz 1885 to 1903. Their telephones came to Australia in 1882 as a result of a contract placed by the NSW Electric Telegraph Department for instruments from a number of manufacturers to be evaluated for the fledgling telephone service in NSW'

This information quote comes from September 1999 Australasian Telephone Collectors Society Newsletter.

It is also quoted in the attached article (in Scienceworks supplementary file) extracted from Australian Historic Telephone Society newsletter no. 219, June 2001. It is attributed to Ric Havyatt. Ric possessed 2 different, original, battery intercom models (in-house phones) one of which features a round-paper label on the front: 'PATENT, M THEILER & SONS, LONDON', similar to what the line instruments had, (Scienceworks has a line instrument, with the round recess for this paper label, which is missing) and he also has one with gold transfer lettering on it, including the word London.

Ric Havyatt sourced his information about the Theiler operations from several places:
1) British Post Office Directory ‘of about 1881’
2) History of the Telephone in NSW by Jim Bateman, of Australasian Telephone Collectors Society, Sydney. Privately published 1980, reprinted 1997 by the Australasian Telephone Collectors Society.
3) Archive material held by former Sydney Telecom Collection (Later the Ashfield collection and now the Bankstown Collection).

Jim Bateman’s book (above), page 12, contains several quotes mentioning Theiler telephones, extracted as follows:

Known NSW Telephones prior to 1887: Instruments known to have been used in NSW by the Electric Telegraph Department prior to 1887, compiled and researched by Mr. A.H. Freeman. Known contracts let for Theiler Magneto Telephones. [also] report by Manager Telephones 1882 lists the following transmitters in use: Theiler. Diary of G.F. Kopsch (Chief Mechanician of NSW Electric Telegraph Department: [includes reference to] Theiler [telephones].

Note: These Theiler telephones would have been line instruments (the business of that department) as opposed to intercom (or ‘battery call’ telephones) which were privately installed. deduction from experience and general research by Linley Wilson.

Additional Evidence: Linley Wilson and Scienceworks collection are both in possesion of Telegraph relays branded M. Theiler and Sons, London. Linley Wilson’s restored Theiler Magneto Line Instrument (almost identical to Scienceworks’ exhibit) carries a small rectangular, xylonite badge between the bell gongs worded M. Theiler and Sons London (refer AHTS Newsletter extract, No. 219, in Scienceworks Supplementary File, for details regarding the sourcing of this from a ruined relay base, and the decision to affix it to this restored telephone)

Examples of Spoon Receivers, identifiable as Theiler receivers are in the Sydney Ashfield collection; labelled as such by the G.F. Kopsch referred to above.

Kevin Graham, NSW collector and member of Australasian Telephone Collectors Society (PO Box 396 Moorebank NSW 1875) possesses a substantially complete magneto line instrument identical to Linley Wilson’s restored example. (The missing parts in Linley Wilson’s were copied exactly from it by engineer Ric Havyatt (Australasian Telephone Collectors Society and former Siemens engineer, referred to above) - except for genuine receivers, sourced separately by Linley Wilson - see AHTS Newsletter 219, extract attached for full story).

Use in Melbourne and Victoria:
Tasmania’s superintendent of telegraphs, Robert Henry, also crossed Bass Strait to see the Melbourne Telephone Exchange Company in operation. [Melbourne Telephone Exchange Co. was registered in July 1880, as a private company]. He found ‘several forms of telephone in use’: at the telephone exchange the Edison-Bell, solely, and on private lines between government departments and other offices, forms such as the British or American [? sic.] Crossley, Gower-Bell, Theiler and others.

Sourced From: Clear Across Australia: A History of Telecommunications. by Ann Moyal, copyright Telecom Australia, 1984, published Thomas Nelson Australia, p.76. Noted by Moyal as quote from Report of Superintendant of Telegraphs, Tasmania, 1881.

Also: The original, wrecked phone for Linley Wilson’s Theiler restoration project (refer attached extract from AHTS Newletter no. 219) was sourced in Melbourne.

Receivers: As mentioned above, the Sydney Ashfield collection has examples of identifiably Theiler receivers labelled by G.F. Kopsch. No receivers were present on any of the telephones mentioned in Australain private collections, until 3 were sourced by Linley Wilson, via other collectors (all found in Australia). Refer AHTS issue 219 for details on acquisition and restoration. The Swiss PTT museum colour print of a similar telephone shows the external ring magnet type of spoon receiver, also identified as such in a photo, from their musueum brochure (no title available, Linley Wilson only has incomplete photocopied extracts obtained third hand from Italy).

Receivers on Linley Wilson’s restoration are of both the external and internal ring magnet types. Note: a considered opinion by comparison of case details and other features by Linley Wilson and other collectors led to the deduction that the internal magnet receiver was a variation of the external magnet type, which is also the type shown on the Swiss museum phone in the colour photo (annotated ‘Print One’ on reverse).

Concluding remarks; It is Linley Wilson’s considered opinion, in conjuction with Ric Havyatt, that there is sufficient similarity between Ric’s marked, English factory, intercom phones and the line instruments of Kevin Graham and Linley Wilson to justify the conclusion that the two line instruments also originated in England. Hence they must have been made between 1881 and 1882. (I would think that all the line phones supplied to Australia were supplied from London, because the first NSW contract for telephones for evaluation purposes was placed in 1881. Quote: Ric Havyatt, Australasian Telephone Collectors Society, Sydney)

Note: dates for the English factory operation of Theiler are confirmed by the third attached page, of three (Scienceworks supplemetary file), extracted from a Swiss PTT museum brochure, listing various telephone manufacturers and their dates.

It is also suggested that the policy of Colonial administrations was to largely order from British or American manufacturers (Ericsson Sweden being an exception, admittedly). Refer the details in Jim Bateman’s book, quoted above- the pages noted list other companies whose phones were imported to NSW prior to 1887, and these were all British or US sourced.

The Theiler line instrument owned by Scienceworks was acqired in 1916 from a PMG source and was thus most likely used in the Melbourne area. As the PMG was not established until after Federation, it may be assumed that this phone was one of the Melbourne Telephone Exchange Company’s instruments (see above) that was eventually taken over by th PMG, in accordance with their practice. Deduction from general knowledge of PMG practices by Linley Wilson.

The presence of round, English-text labels on Ric Havyatt’s intercoms and Kevin Graham’s line instrument (Theiler’s Loudspeaking Telephone) strengthen the case for English manufacture. Interstingly, the text of the label on the phone from the Swiss Museum is also in English, and the portion visible in ‘Print Two' (annotated on reverse) includes the words Theiler and London.

‘Print Two’ also illustrates the correct mouthpiece missing from the Scienceworks instrument- see below.

Comparisons Noted between the Scienceworks Thieler Line Instrument and those owned by Linley Wilson and Kevin Graham:

The two line instruments owned by Kevin Graham (substantially original) and Linley Wilson (mix of original parts and replicas expertly copied from Kevin Graham’s) are to all intents and purposes, identical. Certain differences between these two and the Scienceworks instrument were noted by Linley Wilson, as are commented upon below.

1) The Scienceworks Thieler phone has no round paper label on the front, only the depression where one would have been. Linley Wilson’s partly-replica phone did not have one either, but one was copied from Kevin Graham’s instrument. An annotated facscimile of this label is included with this document as part of the material in Scienceworks Supplementary File. This is the only label extant in Australia (so far as is known to date) for Line Instruments, and it does not mention the word London (Theiler’s Loud-Speaking Telephone) although the similar-size label on one of Ric Havyatts intercom instruments does mention London (M. Theiler and Sons, London).
2) The presence of a push button on the bottom of the baseboard of the Scienceworks phone suggests a later circuit design than that of the two privately-owned instruments, neither of which incorporates this feature. Without having analysed the circuit of the Scienceworks phone, it is likely that this button ‘cuts out’ the bell of its own phone when the generator is used to ring the exchange or distant phone. Deduction based on general knowledge of period mgneto circuits.
3) Likewise, the presence of a knurled-wheel-spring-tensioner on the return spring of the switchook suggests a later model of the instrument, as this feature is absent on the two privately-owned phones. (It is however present on the telephone photographed from the Swiss Telecommunications Museum though not visible in the prints attached to the supplementary file) Deductions based on the general principle that older telephone technology is usually simpler.
4) It appears that the Scienceworks instrument was not originally equipped with the ‘spoon’ receivers referred to above, and featured in the (poor quality) 3-page, photocopied, documentation from the Swiss telecommunications Museum. The Scienceworks instrument has a moving FORK on the hook-switch, as well as a fixed FORK on the RHS to take a second receiver (common feature of period telephones). No receivers of any type accompany the Scienceworks instrument. The privately- owned instruments feature serpentine, single HOOKS on either side (fixed and moving) to take the spoon receivers’ hanging loops. The two types of receivers and fittings are not interchangeable. (The colour ‘Print One’ from the Swiss PTT Museum shows the ‘spoon’ receivers and serpentine hooks on their [slightly different] instrument.) It is suggested that these differences also mark the Scienceworks phone as a later model than the two privately-owned models. Deduction based on a knowledge of historical receiver development.
5) The Scienceworks instrument has a modified, metal, Western Electric (USA) metal mouthpiece from about 1920 fitted to it, in place of the original (presumed lost or broken). The original mouthpiece would have been of ebonite material, and of a larger end-diameter. ‘Print Two’ from the Swiss Telecommunications Museum gives an idea of what would originally have been fitted.
6) The fixed electrodes of the carbon pencil transmitter on the Scienceworks instrument are in some way different to those affixed to bot Australian, privately-owned instruments, and also are different from those in the Swiss PTT Museum instrument. All of these latter three instruments employ ‘half-carbons’, (ie. cylindrical carbon rods cut in half lengthways), glued to the cork diaphragm, as the fixed electrodes. These are shown in ‘Print Three’ in the supp. file, being the Swiss Museum instrument, and representative of the two in Australian private collections. The Scienceworks instrument, by contrast, appears to have copper, fully cylindrical rods glued to the diaphragm, with a wire soldered along the top, of each, as the fixed transmitter electrodes. It is not clear whether this was a later factory development, or a PMG?Aust. colonial departmental modification.

In all cases, the moving/bridging electrode consisted (it is deduced) of a ‘half-carbon’ glued to a brass block, and hung by string from a hook on the top-most screw of the transmitter-diaphragm-fixing ring inside the door. This vital item is missing on both Aust. privately-owned instruments, and also on the Swiss instrument, which, judging by ‘Print Three’ is also missing its hook. This item is only present on the Scienceworks instrument- loose in the case- unable to be fixed in place until the phone is stood up vertically- and, consequently, easily lost!

Linley Wilson, Melbourne, March, 2004.



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