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Manual Calculators This group of
machine are calculating machines comprising all non-printing (listing) machines.
Typically called Key Driven Calculators at Burroughs. The
first machines of this type were built by Dorr E. Felt, marketed by the Felt and
Tarrant Manufacturing Company for many years. Called the Comptometer by Felt, Burroughs referred to this
type machine as the key-driven calculator. The
key-driven type machine did not print, and while it was often used as an adding
machine, it developed into a special purpose machine in later years. The machine was exceedingly fast and experienced operators could easily
outrun an operator on a full keyboard or 10-key adding machine. The efficient operation of these machines required an experienced
operator who often received a high salary. The
machine was produced over a very long period because of its unique capabilities
and was most often used to verify product delivery lists from delivery routes,
such as home dairy delivery, where extending totals was a repetitive task. Later
models of the machine, called a duplex design, could hold a running total in a
second set of dial wheels while the primary wheels continued to add and subtotal
amounts that could be transferred at any time to the running total. A side note, Burroughs copied the Felt design for its first models and was sued for patent infringement by Felt and Tarrant who prevailed in the suit. As a result, Burroughs totally redesigned their machine and went on to compete with the Felt machine for decades. Class 5 (Shoebox
square-corner design) –
Key-driven, non-listing (no printer), calculating machine with single register
(simplex) Date Range -- 1911-1914 Original Price -- $200-$300 Today’s
Value -- $75-$200
Old construction - rare
Front view - note the old style lettering
Nice picture with
instruction manual Class
5 (round corner design) –
Non-listing, key-driven, calculating machines with single register
(simplex) Date Range -- 1915-197x Original Price -- $200-$300 Today’s
Value -- $50-$150
Very narrow machine - actually quite popular
Most were hand operated for clearing
Position was everything, here are the extension legs often used. Class 5 Electric – Non-listing, key-driven, calculating machines with electric key-actuation and clearing. These machines include both simplex (one register) and later duplex (two register machines). Additionally, a simplified subtract method was introduced on the simplex electric machines in 1936. Date Range -- 1928-197x Original Price -- $200-$300 Today’s
Value -- $50-$150
This model was power operated, both the keys and the clearing. This specific machine also included a simplified subtraction capability (see red keys in front part of keyboard)
Class
5 Duplex – Non-listing, key-driven, calculating machines with two registers Date Range -- 1933-197x Original Price -- $400 Today’s
Value -- $100-$200
Style 51055 (Calculator, 10 columns, 5 power, 5 duplex)
Newer machine, about 1955 |
