In the beginning calculating machines were unique pieces, hand-made and artful
"Curiosities" - Gifts for Kings to entertain their court. With the rise of the
industrial era the demand for calculating machines increased. In 1828 the first
mass production, a  STEPPED DRUM  machine, was made by Charles Xaver Thomas in
Colmar. The calculator was based on a principle invented by Gottfried W. Leibniz
in 1700. Also 1920 machines using this principle were produced, eg. the »T.I.M.«.

In 1872 an American, Frank S. Baldwin, patented the PIN WHEEL - in 1874 a Swede,
Willgodt T. Odhner working for Nobel in St. Petersburg / Russland, had the same
idea and got a patent in Europe.  With these calculating machines one could add,
substract, multiply and divide. They were smaller, lighter and cheaper than the
Stepped Drum machines and became very popular.  An important feature of Odhner's
invention  was  time-splitting  the  10s-CARRY  which  enables  an  addition  of
99999999 + 1  without friction problems.  In  1892  Odhner licensed his patent
rights to the sewing machine company GRIMME, NATALIS & CO. in Braunschweig. This
company later changed its name to »BRUNSVIGA« and became very successful.  After
the "October Revolution" in 1917, Odhner was forced to leave. His factory in St.
Petersburg was dismounted and rebuild in Moscow. Feliks Dzerzhinsky, head of the
KGB, was put in charge of the factory and renamed the machines »FELIKS«.  Odhner
moved to  Goeteborg / Sweden  and continued  to produce calculators  under the
trade mark  »ORIGINAL-ODHNER«. 

Other companies  FACIT, SCHUBERT, THALES, TRIUMPHATOR, WALTHER ...  joined the
growing calculator market  and improved on Odhner's design.  In the beginning
the COUNTER for crank-turns had no 10s-carry feature.  TRIUMPHATOR was the
first company with  10s-Carry Counters  on the market,  enabeling "Short-Cut
Multiplication" ( instead 17 only 3 crank-turns for multiplying  89*89 ).

A true genius in the field was the inventor  Christel Hamann  of Berlin.  His
motorized  PROPORTIONAL LEVER  Principle of 1910  was marketed by  MERCEDES
BUEROMASCHINEN.  In 1925  he invented the  SWITCHING-LATCH-WHEEL.  These
calculators, which looked like Odhner machines, where produced under his name
manual HAMANN-MANUS and also the motorized MERCEDES-EUKLID calculators, had
automatic division.  His motorized  »Automat-S«  is impressive:  Division
and  "Short-Cut Multiplication"  are incorporated as  "Hardware Algorithms".

In 1912  Frank S. Baldwin  together with  Jay R. Monroe  in the USA invented
another mechanic for calculators, the SPLIT STEPPED DRUM.  With their light-
weight, full-keyboard machines, MONROE captured the market.  The calculators
had a very interesting mechanic for its  10s-CARRY.

Machines with 4 basic arithmetics are important for engineering calculations,
but PRINTING ADDING MACHINES are a necessity for accounting.  Both BURROUGHS
and VICTOR in the USA were very successful in this market. They started with
"Full" keyboards and produced later also "10-Block" keyboards  we are still
using today.  See the principle of converting the serial input into parallel
processing in the figure  10-BLOCK KEYBOARD.

A very different type of high-speed adding machine is the  COMPTOMETER,  an
invention of  Dorr E. Felt in 1885.  William S. Burroughs  also had the same
idea at this time.  In  the  patent struggle  Felt won  -  but  in the end,
BURROUGHS  became the more successful maker of calculating machines.

One of the most interesting calculating machines also has a very interesting
history.  The CURTA is the world smallest mechanical full-function calculating
machine. Kurt Herzstark invented it while he was a prisoner in the Buchenwald
Concentration Camp. The story was published with amazing pictures of mechanical
details by Cliff Stoll in  »Scientific American« 01/2004.  The CURTA works with
a modified  STEPPED DRUM.  It was a product of its best in fine-mechanics and
is today in high demand for collectors of calculators around the world.

"Enjoy to visite the On-Line Museum!"

      Choices (1)  START Tour A ... Z in the Department CALCULATORS

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"THANKS!" to Dr. Michael Giehl from FU-Berlin / Klinikum  » Benjamin Franklin «.
In the years 2000..2003 "Mikey" established the foundation for this  hand coded
HomePage.  My  "Take-Over"  was easy with his friendly help. 

© C.HAMANN            11/11/11