From The Ashes of Buchenwald Came The First Hand Cranked Mechanical Calculator.

Picture from https://history-computer.com 
page on Curta

When we think about calculators, we think about the hand held ones that came out in the 1970's or we might vaguely remember those adding machines with the rolls of tape. We don't think of anything that might have come out of World War II.  I came across an article a couple ago on this exact topic.  

Picture if you will, a small pepper mill sized hand held calculator in the hand of a person in a black and white photo. First released in 1948, the Curta hand cranked mechanical calculator was the choice of people for the next two decades until the electronic versions hit the market.

The first calculating machines were big and heavy and as such were really desktop versions.  In 1902, Curt Herzstark was born into a family whose business was to produce and sell desktop calculator and other office equipment.  By the 1930's Curt ran the family business and travelled across Austria, Hungary, and Czechoslavakia selling machines to banks and factories. If you've seen Hidden Figures, you'll have seen one of these machines used by some of the women.  One thing he heard from many of the people such as architects, customs men, and others who wanted something that was more portable.  

After hearing all of his clients comments, he knew something needed to be done.  The calculators would need to be redesigned because the parts could not just be reduced in size and still have the machines work. He began by picturing how the new handheld calculators would look so that it could be used.  He decided it had to be a cylinder, and there had to be numbers on sliders that one could input values, one digit as a time.

So by 1937, he had worked out the design, determined how the parts should go together to work and was ready to create a prototype but the storm cloud blowing across Europe came hit his country and Hitler took over. Although his father was Jewish and his mother catholic, he was concerned but the Nazi's allows the factory to continue as long as they produced tools and machines for Germany.  This was fine until charges of supporting Jews and having an affair with an Arayan woman were lodged against him.

This resulted in his arrest and being sent to Buchenwald concentration camp where conditions were brutal.  Curt was assigned to work in a factory producing V8 rocket parts.  One of his supervising engineers heard rumors of his hand held mechanical calculator. Curt was told that he could work on his machine and when the war ended in victory.

This one thing gave him hope of surviving the conditions and he was able to draw actual plans for his machine before the Russians liberated Buchenwald in April 1945.  Curt walked to the next town over and took over an abandoned factory where he created a prototype of his machine from the plans he'd carried folded up in his pocket.

When the Russians overran the village, he escaped to Vienna with both the prototype and his plans.  In post war Europe, countries were struggling to begin again.  Luckily for him, the government of Liechtenstein found his machine interesting and they set up a company for him.  He used this company to produce his Curta hand held mechanical calculator for sale in 1948. It could perform addition, subtraction, multiplication, and division, find roots and powers.   The machine was well received and loved by all who used it because it provided the precision and mobility they wanted. He passed away in 1988.

It is said that around 150,000 machines were sold between 1948 and 1972 when small hand held electronic calculators took over the market.  It is still possible to find second hand Curta's being sold but they can be quite expensive. The other place to find these machines are in museums across the world. The world is lucky he survived the horrors of Buchenwald so he could make his mark on the world.  Let me know what you think, I'd loved to hear.