The Rocky Road to the Curta Pocket Calculator

Curt Herzstark had to overcome quite a bit to make his little pocket calculator. 

The portable calculators of my childhood are now largely obsolete. Students still tote around TI-83s, though I have a feeling that they are not long for this world. Our phones have sophisticated calculators, as does just about everything else with a screen. The ability to make quick calculations mindlessly with the aid of a computer has become normal. Our fully taking for granted accessible number crunching machines really began in the early 70s when digital calculators became widely available. 

Before the advent of cheap pocket calculators,one either had to work the problem out on paper, use a bulky and limited desktop adding machine, or have access to an extremely expensive large computer usually found at wealthy corporations or universities (One could buy 25 Chevy sedans for the price of 1 Bendix G-15 computer). The only really viable option for a fast handheld computer was the Curta mechanical calculator. There were two models, the Curta I and the Curta II. The I was capable of calculating results 11 digits long including decimals. The II was capable of 15 digit results. The Curta can be used to multiply, divide, subtract, add, find square roots, and a number of other complex functions.

Operation of the Curta takes practice and is a bit confusing, but for professionals, from Engineers to race car drivers, it was a boon for rapid calculation. My great uncle, a self-taught engineer and architect, kept his Curta on his living room mantle to show off to visitors. It really is an impressive little thing. It's surface is covered in sliders, a crank, dials, and little number wheels that swing around as the operator uses it. My uncle reveled in his guests astonishment as he whirled the crank on his little calculator and solved complex mathematical problems. I once asked if I could hold it. He said no. 

Just as impressive as the machine itself is the man who invented it. Curt Herzstark was a Austrian Jewish engineer who came from an engineering family. He grew up to run his father's company, Rechenmaschinenwerk AUSTRIA Herzstark & Co, which specialized in making and selling calculating machines. Most calculators were large hefty desktop devices, the most famous perhaps being Burroughs Adding Machine (invented by the grandfather of writer William S. Burroughs). By the outbreak of WWII, Herzstark had developed what was to become the Curta calculator but was unable to put it into production before the Nazis forced his family's company to cease normal operations to manufacture precision instruments for the Third Reich. 

Herzstark himself was in a very risky position, his father being a liberal Jew and his mother a Catholic. Despite this, things went relatively smoothly for his company for a few years. Production came to a halt in 1943 when some of his employees were caught by the SS listening to English radio programs and transcribing them with a typewriter. The employee who owned the typewriter was executed. Herzstark was thrown into a series of horrendous prisons before ending up in the Buchenwald Concentration Camp. Herzstark, though deemed an "intelligence slave" was first assigned to hard farming labor, where his health began to fail.

Herzstark was able to recover somewhat when transferred to the Gustloff forced labor factory where he made precision tools. He was ordered to create the finest calculating machine, which would be presented to Hitler upon Germany's triumph. Herzstark realized that this project would make him valuable enough to keep alive and began working on Sundays and evenings with pencil and paper to draw meticulous plans for his calculator. By the time the camp was liberated in 1945, he had nearly completed the plans for the complex machine, all from his memory. 

He took his plans to a factory near Weimar, Germany. Due to the intense detail of his plans, the company was able to make three working prototypes in just eight weeks. Unfortunately, the factory was in what would become the Russian occupied zone. Herzstark was rightfully frightened of being detained and sent to Russia, as had already been done to other skilled people, so he fled to Vienna. Before traveling, he completely disassembled the three calculators so they would appear to be nothing more than miscellaneous parts. After a few years of setbacks, including his investors (the prince of Lichtenstein among them) trying to steal his machine from him, the Curta calculator finally went into production in 1948.

Herzstark settled in Lichtenstein, where his calculator was produced, and lived there until his death in 1988. The Curta was manufactured until 1972, when cheap digital units made it obsolete. Not much is known about Herzstark's later life, as he was a very private man. By the end of their production run, 140,000 Curta calculators had been manufactured. Near the end of their production, a Curta could be had for around $135. They are perhaps one of the only adding machines of their era that have become substantially more valuable with age, fine examples now selling for well over $1000.