Curta

The Curta is a hand-held mechanical calculator made by Curt Herzstark. It is very small and fits easily in the palm of your hand. Because of its shape and how it works, people called it the "pepper grinder" or "peppermill." Some even called it the "math grenade" because it looked a little like a hand grenade.

Curta calculators were thought to be the best portable calculators for many years. They were used until electronic calculators became popular in the 1970s. These tiny machines could do complex math calculations without needing electricity, making them very useful for scientists, engineers, and mathematicians.

History

The Curta was created by Curt Herzstark in the 1930s in Vienna, Austria. He designed a small, clever calculator that could do more than just add numbers. It could also subtract using a smart math trick. This design was much simpler than older calculators.

Herzstark’s work was interrupted when he was taken to a difficult place during a hard time in history. While there, he was allowed to keep working on his calculator idea. After he was freed, he built the first working models. With help from a prince, production began in a small country. Even though some people tried to take advantage of him, Herzstark kept working, and the Curta became a famous portable calculator until electronic ones took over in the 1970s. Many people still collect these amazing little machines today.

Cost

The Curta Type I was sold for $125, and the Type II for $175. Even though most Curtas worked well, some people tried to take them apart, which made them hard to put back together. These calculators are now very interesting to collectors; in 2016, they were sold for about US$1,000, with some special ones reaching up to US$1,900.

Design

The Curta was inspired by earlier machines created by Gottfried Leibniz and Charles Thomas. It used special wheels and a stepped drum to do calculations.

To put in numbers, you moved slides on the side of the machine. Turning a handle added numbers together. Lifting the handle up a little before turning it let you take numbers away instead. To do more complex math like multiplication or division, you had to move parts of the machine and turn the handle many times.

Models

The Type I Curta calculator has eight digits for entering numbers, a six-digit counter for steps, and an eleven-digit counter for results. It was very light, weighing only 228 grams. A later model made in 1969 weighed a bit more, at 245 grams.

The bigger Type II Curta was introduced in 1954. It has eleven digits for entering numbers, an eight-digit step counter, and a fifteen-digit result counter.

Uses

The Curta was a favorite tool for people in sports car rallies from the 1960s to the 1980s. Even when electronic calculators became common for other jobs, racers still used the Curta for figuring out times and distances because electronic calculators were not tough enough for the bumps during races.

Pilots also liked the Curta before electronic calculators were common. It helped them make exact calculations, like checking the weight and balance of their planes, which are important for safe flying. The Curta let pilots double-check their work easily.

Collections

The Curta calculator is very popular among collectors and can be found on many platforms. A Swiss entrepreneur named Peter Regenass has a large collection of mechanical calculators, including over 100 Curta calculators. Some of his collection is displayed at the Enter Museum in Solothurn, Switzerland. In 2016, he donated a Curta calculator to the Yad Vashem Museum in Jerusalem.

Popular culture

The Curta appears in William Gibson's book Pattern Recognition from 2003. In this story, it is both a historic computing tool and an important item that people trade.

In 2016, someone named Marcus Wu designed a Curta that could be made using a 3D printer. However, the technology at that time could not make it small enough, so the printed version was about the size of a coffee can and weighed around three pounds.