Do you know anything about how the origins of the GE monogram relate to that of BTH (British Thomson-Houston) in the UK? I have never been able to find any documentation as to which of them was used first. If my attached image has worked correctly you will see how similar they are and it seems likely that one is based on the other.
Since BTH was formed from American T-H, later to become GE, it's perhaps not surprising that they used to work together very closely and had access to each other's patents, trade marks (eg. Mazda) so it is possible one company adopted the other's logo. Even the casting numbers on old BTH machines in the UK are identical on American machines still running in some old GE plants so there was clearly a lot of collaboration back then.
The plant I did my college placement at is a GE factory today, but originally it was a BTH lamp works. Many employees and retired staff who have worked their whole lives there firmly state that the BTH logo pre-dates that of GE, having been first used in 1896, but I have never found any written proof of this. The main story there is that someone in GE's fan division produced the GE script while bending up a piece of wire to decorate the centre of a fan guard, and that it was used as the plain letters for many years but later they adopted the ring from BTH logo, added a fourth 'tail' and placed it around the GE script. So maybe the GE script in the centre predates BTH but the present circular GE logo was a later development?
Anyway if you know anything about the history of this I'd be very interested to hear your comments!
FYI you can find an excellent clarification covering much of the highly complex series of mergers that took place in the history of UK lighting firms on GEC's website at
http://www.gec.com/about_marconi/heritage/It includes the amalgamations and takeovers involving famous lamp brands such as BTH-Mazda, AEI, GEC, English Electric, Robertson, Metropolitan-Vickers, Siemens-Edison-Swan, Ediswan, Ekco, Ensign, Atlas and Thorn Lighting. Today the light source divisions of all of these have through various routes ended up in the hands of GE and Osram and this site makes a good attempt to document the main changes. There are some slight differences though as the timeline charts the history of the core businesses and in some cases, the lighting divisions changed hands separately.
