A recent typewriter purchase (the Tippa) had a nice surprise in store for me on the inside of the case. A dealer's sticker for Metyclean of London. The most interesting feature of this being the telephone number which was TAT 9438. TAT? What kind of telephone number is that?
Let us dial back a bit (so to speak). In the earliest days of telephony most phone calls were directed via an operator, especially if the number you wanted was on a different telephone exchange to the one you were connected to. In the 1950s this changed with the arrival of Subscriber Trunk Dialing (though it took a couple of decades to be fully rolled out). Each exchange had it's own three figure code which you would dial first, then the individual number that you wanted to reach. These three figure exchange codes were described in letters. TAT was therefore the code for TATe Gallery! Now, the telephone exchange code was really a number (828 in TAT's case) but letters were easier to remember.
But telephone dials have numbers not letters, so how could you dial TAT? Simple, the telephone dial actually did have letters too! So if you wanted to dial TAT you would actually be dialling 828.
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| To dial TAT you would dial 8(T) 2(A) 8(T) |
By the 1970s the use of letters in telephone numbers was dying out, the reason being that exchanges were running out of numbers for their original code and therefore needed to have more codes allocated. However, here and there the numbers survived on old signs into the following decades. Below is an example of an ERDington exchange number on a shop sign in the late 1990s. Unfortunately this sign has now long gone.
