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 In 1963
some Martins’ machine room staff in Liverpool and London change from listing
items on mechanical adding machines and statement printers, to using the
latest encoding machines to print, in magnetic ink, a monetary value along
the bottom of each cheque. Together
with other information already printed on the cheque, such as a serial
number, the sorting code number that identifies a particular branch of
Martins, and most importantly an account number, the cheque is thus equipped
to be read and sorted by machine, enabling funds to be quickly removed from a
customer’s balance. The allocation of
account numbers is met with some resistance by customers who feel that
banking will become impersonal – up to this point not even the customer’s
name has been printed on a cheque, and staff have to rely solely on
recognising and comparing a customer’s signature with branch records! A sophisticated system of account numbers
involving a complex mathematical check of the account number against the
sorting code, has been developed for all banks, and this effectively prevents
the customer from being debited for a transaction that isn’t theirs.
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A cheque is placed in the encoding compartment of a National Cash
Register Company (NCR) encoding machine.
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The principles of electronic reading, showing how characters printed
in magnetic ink are sensed and interpreted. Seventy “blocks” are scanned by
powerful logic circuits to interpret each of the fourteen permitted
characters in the E 13 B typeface.
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 The
multi-channel reading head of the IBM READER/SORTER machine breaks up the
characters into 10 horizontal elements. Seven separate readings are made as
the character passes under the reading head, so that each numeral or special
character is divided into 70 blocks, or sensing areas. The presence or
absence of magnetic ink in each of these sensing areas is recorded in an
electronic register, which therefore builds up an image of the printed
character. Powerful logic circuits compare this image with the perfect
character, and with the thousands of permitted variations. Some variation is inevitable, and the
machine’s usefulness would be very limited if only perfect reproductions were
accepted. It therefore rejects only
those images in the electronic register which could be related to more than
one of the 14 possible characters. The characters which make up the E13B
typeface have been carefully designed after exhaustive analyses of
comparative shapes. Each is as
different as possible from all the others, yet retains its legibility for the
human reader.
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