Buy Curta Calculator Replica
The estimated number of Curta units produced, according to a factory production list acquired by the website VCALC.net, which has heavily documented these devices. (Herzstark, who was critical of the company that ended up producing them, said that if they had been marketed properly, they could have sold in the millions. He had put the production estimate in his oral history around 150,000 to 160,000, so there could always be more.) Online fans of the mechanical calculators have gone to the step of aggressively tracking the serial numbers on the bottoms of the devices, which seems like the perfect kind of hobby to have around a calculator.
buy curta calculator replica
The Curta is a hand-held mechanical calculator designed by Curt Herzstark.[1] It is known for its extremely compact design: a small cylinder that fits in the palm of the hand. It was affectionately known as the "pepper grinder" or "peppermill" due to its shape and means of operation; its superficial resemblance to a certain type of hand grenade also earned it the nickname "math grenade".[2]
The Curta was conceived by Curt Herzstark in the 1930s in Vienna, Austria. By 1938, he had filed a key patent, covering his complemented stepped drum.[3][4] This single drum replaced the multiple drums, typically around 10 or so, of contemporary calculators, and it enabled not only addition, but subtraction through nines complement math, essentially subtracting by adding. The nines' complement math breakthrough eliminated the significant mechanical complexity created when "borrowing" during subtraction. This drum was the key to miniaturizing the Curta.
Curtas were considered the best portable calculators available until they were displaced by electronic calculators in the 1970s.[1] The Curta, however, lives on, being a highly popular collectible, with thousands of machines working just as smoothly as they did at the time of their manufacture 40, 50 or 60 years previous.[1][6][7]
The Curta was popular among contestants in sports car rallies during the 1960s, 1970s and into the 1980s. Even after the introduction of the electronic calculator for other purposes, they were used in time-speed-distance (TSD) rallies to aid in computation of times to checkpoints, distances off-course and so on, since the early electronic calculators did not fare well with the bounces and jolts of rally racing.[1]
The Curta was also favored by commercial and general-aviation pilots before the advent of electronic calculators because of its precision and the user's ability to confirm the accuracy of their manipulations via the revolution counter. Because calculations such as weight and balance are critical for safe flight, precise results free of pilot error are essential.
The Curta calculator is very popular among collectors and can be purchased on many platforms. The Swiss entrepreneur and collector Peter Regenass holds a large collection of mechanical calculators, among them over 100 Curta calculators. A part of his collections is on display at the Enter Museum in Solothurn/Switzerland. In 2016 he donated a Curta calculator to the Yad Vashem Museum in Jerusalem. [9]
The engineer Roberto A. Guatelli manufactured many replicas for IBM, Digital Equipment Corporation, and other customers (for details, see The Model Maker of Leonardo da Vinci, Blaise Pascal, and Charles Babbage.
In 2018, Parmela McCorduck donated to Carnegie Mellon University (CMU) a collection of calculating machines, including an early Thomas Arithmometer, a three-rotor and a four-rotor Enigma, and a Guatelli replica of the Millionaire direct multiplier. In December 2018, I was trying to find out more about the Italian model maker. A few days ago, Mary Catharine Johnsen from CMU let me know that their collection also comprises Guatelli rebuilds of Pascal, Leibniz, Adix and Webb.
The Traub-McCorduck Collection, which is home to five Guatelli reproductions, is named in honor of Parmela McCorduck's late husband, the computer science pioneer Joseph Traub. In 1988, the couple bought the five replicas from Guatelli.
The only surviving copy of the Leibniz calculator dates from the 1690s, and is kept in Hannover, Germany. Leibniz's calculator was the world's first mechanical calculating machine capable of all four basic operations (for details, see Meilensteine der Rechentechnik).
In the IBM archives, you can find several Guatelli replicas (including the Pascaline). It is not known who is the author of the calculating machines of Leibniz, Leupold/Braun/Vayringe, Morland, the analytical and the difference engines of Charles Babbage, the difference engine 2 of Edvard and Pehr Scheutz. Unfortunately no information is available.
Guatelli was engaged from 1951 to 1961 for Thomas J. Watson Sr., the founder of IBM; after that, he opened a workshop in New York. According to Jim Strickland, Guatelli's nephew, Joseph Mirabella began working with IBM in 1964. He continued the business after Guatelli's death until 2005. Mirabella had donated the Da Vinci models to the Long Island Science Center, Riverhead, New York. Nathan Myhrvold of Intellectual Ventures is said to have acquired the remaining replicas of calculating machines. Further information is still pending.
There are some museums with Leonardo da Vinci models, such as those in Vinci, Florence, and Milan, Italy. Handmade replicas by Roberto Guatelli and Joe Mirabella are exhibited at the Long Island Science Center, Riverhead, NY. According to Marta Montagnaro in the Museo Leonardiano di Vinci, there is only one Guatelli model in that museum: the Carro automotore (self-propelled car), 1952. 041b061a72