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Curt Herzstark: The Inventor Behind the Curta Calculator

Early Life and Family Heritage

Curt Herzstark was born on January 26, 1902 in Vienna, Austria. His father, Samuel Jakob Herzstark, was a self-taught engineer and businessman who had founded Austria‘s first calculator factory, Rechenmaschinenwerk AUSTRIA Herzstark & Co., in 1905. The family had deep roots in the calculating machine industry.

Samuel‘s passion for these intricate devices stemmed from his travels to the United States and work selling typewriters and adding machines in Europe. He recognized the potential for improvements to leading calculators of the era like Thomas de Colmar‘s Arithmometer and envisioned building his own superior model.

So Curt grew up surrounded by the sights, sounds, and innovations of his father‘s factory. As a child, he demonstrated calculators at exhibitions and later apprenticed with the machinists. This early mechanical training combined with his innate talent for envisioning elegant technical solutions set the stage for Curt‘s later achievements.

Education and Early Inventions

While Curt studied business and sales at his father‘s urging, his true interests were in fine mechanics and precision instrument design. In 1922 after graduating trade school, he eagerly returned to the family calculator plant to learn all facets of the trade.

Samuel soon sent Curt to broaden his expertise at calculator factories in Germany for a year. When he returned to Vienna, Curt applied this knowledge to make major sales organization improvements before turning his focus to enhancing the devices themselves.

At just 26 years old in 1928, Curt patented his first invention – the Multimator. This novel machine could automatically add rows and columns in a single pass, making calculations far faster. The young ingenue‘s creation caused a sensation when revealed at a Berlin exhibition.

In the following years, Curt dedicated his efforts to developing a portable, cylindrical calculator which could perform complex math reliably anywhere. By 1938, he had formulated plans and filed a foundational patent for this compact, elegant design. However world events soon intervened, forcing the project aside as war loomed.

Imprisonment and Forced Labor During World War II

The Anschluss marked the end of Curt‘s peaceful innovation in Vienna. As the Nazis annexed Austria in 1938, the Herzstark factory was co-opted to produce armaments. The family endured tremendous hardship under the ensuing Aryanization discrimination. Then tragedy struck when Samuel passed away in late 1937, leaving Curt to guide the embattled business.

Despite currying initial German favor by manufacturing weapons components, Gestapo arrests of Curt‘s workers eventually led to his own imprisonment in 1943. His Jewish lineage and resistance activities were cited as grounds for detainment at the notorious Buchenwald labor camp.

However, the Nazis also saw potential value in Curt‘s mechanical engineering expertise. He was soon transferred to the Gustloff munitions factory in Weimar, where around 4500 prisoners worked in brutal conditions. The gifted inventor convinced his captors to allow him to discretely draft plans for his coveted cylindrical calculator as recompense for his toil.

When Gustloff was leveled by bombs in 1944, Curt was moved to the underground Mittelwerk plant where V2 rockets were produced. There he managed to survive the compound‘s high mortality rate until American forces liberated Mittelwerk in 1945. All told, nearly 3 years had passed while Curt clung to life as a Holocaust prisoner, sustained by his visions for the petite calculating device.

Post-War Business Ventures

Upon returning to Austria after the war, Curt reunited with his family and tried resuscitating the battered Herzstark factory. But disagreements with his brother over patent rights, along with meager finances for manufacturing, soon had Curt seeking fresh partnerships abroad. He found an eager advocate in the Prince of Liechtenstein, leading to the launch of Curt‘s Contina AG calculator company in 1946.

With backing from the royal family, an ultramodern new plant was constructed in the village of Mauren specifically for mass production of Curt‘s calculator. But sadly, he was gradually isolated from management at Contina and resigned after a decade in 1956. Failing to achieve wealth or acclaim commensurate with his inventiveness during his career was a regrettable outcome of both hostile external events and internal company politics.

The Curta Calculator Legacy

Yet while the man was underappreciated, Curt gifted the world one of the twentieth century‘s most extraordinary mechanical calculating instruments. Only 15 years elapsed between his initial 1938 compact calculator patent and Contina completing the commercial Curta in 1953.

This palm-sized mechanical marvel could rival bulky desktop computing machines in speed and accuracy. The Curta performed its astonishing four function arithmetic via an intricate array of gears, levers, slides, and stepped drums – all hand assembled with watchmaker‘s precision.

Inner Workings of the Curta

The Curta‘s compact form was enabled by aclever stacked design in which components were distributed vertically across 7 tiers:

Input numbers were set on digit rings atop the main body, then entered by a side crank. Gears propagated this rotation into the heart of the device – three vertical stepped drums corresponding to the calculator‘s three numeric registers. These central drums featured machined steps used to translate rotations into precise linear movements to enact mathematical operations between numbers. The step drum outputs were finally displayed in rotating result windows at the base.

The Curta‘s capabilities rivaled far larger contemporary electromechanical calculators:

  • Performed addition, subtraction, multiplication, and division
  • 15 digit capacity with guaranteed accuracy up to 10 digits
  • Floating decimal setting
  • Output negative numbers directly with dedicated negation lever
  • Automatic memory features for chained/repeated operations

This performance and reliability made the Curta a trusted companion for engineers, scientists, and financial workers during an era when electronic computing remained temperamental and scarce. Curtas were produced in Liechtenstein by Contina A.G. from 1954 to 1970, with around 140,000 units manufactured in total.

The Curta‘s usefulness persisted well into the 1970s as faster but failure-prone transistorized calculators emerged. But just as slide rules gave way to electronic devices, the last intricate mechanical Curtas were finally rendered obsolete for mainstream math use by affordable, compact digital calculators in the mid 1970s.

Legacy and Rediscovery

While the Curta faded from widespread use, its brilliant design endures as a testament to Curt Herzstark‘s technical vision. The device‘s striking form has made it an icon of late industrial age design. And with functional units still treasured by engineers and collectors today, the story of the Curta calculator continues to inspire new generations.

In the 21st century, these hand-crafted mechanical masterpieces have found renewed interest among designers, steampunk builders, and technology historians. As electronic gadgets become ever more inscrutable black boxes, Curt‘s elegant visible workings and clever integrating of physical and digital principles still provide lessons for human-centered machine invention.

So while never financially rewarded for his contributions, Curt Herzstark‘s perseverance conferred the lasting gift of the Curta on 20th century science and computation. The teachings of his life story and epoch-defining calculator live on to shape new innovations yet to come.

Herzstark‘s Later Years and Legacy

After leaving Contina AG in 1956, Curt Herzstark continued consulting for various companies in Liechtenstein and Germany, applying his expertise to improve typewriter and cigarette lighter designs among other devices. But he did not regain the success or recognition his earlier work merited. Remaining intellectually active but living quietly in his adopted Nendeln hometown, Curt faded into relative obscurity in his later years.

Curt passed away in 1988 at age 86, just 4 years before Contina ceased trading. Survived by his wife, son and daughter, his published writings and patents stand record to his talents for those discovering Curt‘s work today. While lionized overseas, especially in collector circles, broad fame still eludes this Austrian computing pioneer in his homeland to an unjust degree.

Reevaluation of Holocaust narratives has brought some overdue light on technical skills that despotic regimes perverted to weaponized ends, and we must fully acknowledge figures like Herzstark who navigated such grey zones of complicity to survive while minimizing collateral damage. More complete accounting of Curt‘s difficult balancing act working under the Reich could offer perspective both on ethical invention and the human pressures all of us could face during conflict.

Ultimately, Herzstark‘s abiding impact resides in the brilliant mechanical calculating machines birthed of his mind. Each surviving Curta remains a testament to human ingenuity thriving even amidst tremendous personal adversity – both for its inventor and users worldwide who relied on Curt‘s device to enable their own innovations against the backdrop of war recovery and shifting technology frontiers in the post-World War II era.