[Pellseinydd]

I think you may find it is just a manufacturers variant.

The Transmitter No 1 was replaced by a Transmitter No 22 when it was introduced in 1929 at the time the Inset, Transmitter No 10 was introduced.

I have a Tele No 2 dated 1910 made by British Insulated Helsby Cables and it has a Receiver Bell No 1A.

The only different 'Bell' receiver I've got on a 'candlestick' telephone is a 'Receiver, Bell No 4' which has a single coil on a steel armature - not a magnet. Hence when the cap is removed the diaphragm drops off. It is on a Telephone No 72 dated 1913 and fitted with a Dial No 1 - made by Automatic Telephone Manufacturing - the successor factory at Edge Lane, Liverpool when BIHC got the contract for the GPO's first two automatic exchanges which opened in 1912.

Both of the above 'Bell' receivers have a 'groove' in the 'Earpiece No 2' to allow the howler to be heard if the receiver is left 'off hook' and stood upright. The Vocabulary of Engineering Stores' back in the 1940's lists three versions of the 'Receiver, Bell 1a' Mk C & D plus the 4001 - all fitted with an 'Earpiece No 2' whereas the Mk B was fitted with an 'Earpiece No 1'.

Is yours fitted with a No 1 ?

Bell receivers have often had the incorrect earpiece fitted since they left the GPO and moved into preservation.

The other different Bell receiver I've got is nearly thirty years earlier which I was given by the Science Museum who had had it since 1911 according to their records. Same as picture in 1880 'Cyclopedia of Self Instruction' in the section 'Natural Philosophy' ! See attached. The 'Patent' is the UK parent for Bell's telephone and was applied for the ten years from the date until it expired. The US patent was dated March 1876.