Numbering of pre-war TIM machines

In the 1930s some operators were supplied with "Standard" machines numbered in an operator-dedicated series usually starting at 1. However, many other operators received "Standard" machines that appeared to be numbered in a manufacturer's series, not related to the operator. Typically, machines would be numbered somewhere in the range 1-999 either with a suffix letter (usually "A") or without. It is tempting to assume that the manufacturer's numbering system simply started at 1, progressed to 999, then moved on to 1A and thence to 999A. But things were not that simple! For one thing, by early 1937 about 5500 Standard machines had been sold. Even allowing for machines numbered in operators' own series, it seems that the observed manufacturer's numbering series would have been well and truly exhausted by then. From the observation of only a relatively small sample of tickets from pre-war machines, several cases of the same machine number appearing on two different operator's machines have been noted. Two examples involving numbers 795A and 888A are illustrated below. (Other similar cases, but involving numbers without letter suffixes, have also been noted). Based on these observations, it seems likely that manufacture used a numbering system that simply ran from 1-999 and then repeated itself, probably many times. The significance of the letter "A" is uncertain. There are cases where, within a well-defined sequence of numbers, "A" may or may not appear. Could it be that "A" signifies a "Standard" (short-range) machine? It is to be noted that a "P" prefix was often associated with the numbering of "Major" (long-range) machines. Now the illustrations:

Ticket from Nottingham Corporation's machine 795A (not a perfect specimen – but it's definitely a "5" in "795"), followed by:

A ticket from Reading Corporation's machine 795A. Note that the font used for the machine number is the same for both plates. And now:

A ticket from Blackburn Corporation's (B.C.T.D.) machine 888A. Followed by:

A ticket from South Wales Transport's machine 888A. Note that this time the machine number is in manuscript style for both these specimens.

It would be interesting to try and piece together the jigsaw of the manufacturer's numbering system. If you can help in any way, please Click to email me
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