Autarit of Alexander Rechnitzer

We have already examined the single-column adder of Charles Weiss from 1886, which was the first adding device with electromagnetic operation.

In contrast with the abovementioned machine however, the device of the next inventor—Alexander Rechnitzer, was much more sophisticated and was put in serial production, even though in small quantities and without market success. It was the world’s first motor-driven calculating machine and it was also the first machine to embody full automatic multiplication and division.

Alexander Rechnitzer, a German Jew, born in Austria-Hungary Empire (somewhere in CzechoSlovakia) probably in 1879 or 1880, is a holder of numerous patents for calculating devices in Austria, Germany, Switzerland, USA, France, etc. Rechnitzer appeared to be an extremely talented mechanic and versatile inventor, who built his first experimental model at the age of 19. One of his later patents is for talking calculating machine.

Rechnitzer's first patent application was filled in November, 1900, in Vienna, Austria, and described a stepped-drum motor-driven calculating machine. Patent was granted in 1904 (Nr. AT15514B). Several years later this patent will be implemented in the first in the world motor-driven calculating machine, put in serial production by the company Autarit GmbH, of Vienna, under the name Autarit. The machine was in production from 1910 until 1914 in small quantities.

Rechnitzer‘s first machine, the Autarit

Based on and similar to the Thomas machine (stepped drums and 2 rows of setting sliders, one in the lower part and second on the movable cartridge beneath the result windows), this calculator also used an automatic multiplication and division mechanism patented by Rechnitzer, which will be used later successfully in machines like Madas.

For addition, the first number is entered in the lower slots, the machine is set to addition by means of a button, the start key for the motor is pressed and the number is thus transferred into the result mechanism.

For subtraction, the greater number is entered into the result mechanism (numerical wheels), the machine is set to subtraction by means of a button, the start key for the motor is pressed and the remainder can be seen in the result mechanism.

For multiplication, the multiplicand in entered in the numerical wheels, the machine is set to multiplication moving the control lever, the multiplier in entered by means of the setting sliders, and the motor is started, causing the machine to complete the calculation automatically. With each revolution of the shaft, the settings slide, at the first place from the right, moves one digit towards the zero. When it arrives at zero, the carriage is automatically shifted by one place, and now the slide set in this place commences to move automatically towards the zero position, and so on, until multiplication is complete and the result is displayed on the result windows.

Division was done by setting the dividend in the numerical wheels, the divisor in the lower setting slides, then moving the control lever to the divide position, whereupon the machine would automatically complete the calculation.

Rechnitzer‘s last machine

The upper picture shows Rechnitzer‘s final effort to produce a salable automatic four-rules calculating machine. He started the construction of this model in 1912. The pulley on the left end provided for a belt drive. This machine can do automatic shortcut multiplication and full automatic division, and it contains a memory mechanism. The memory makes it possible to install a second multiplicand and multiplier while the machine is making the last preceding multiplication, and to install a new dividend during the computation of the last preceding division.

Later on Rechnitzer moved to live in Berlin, Germany. Starting from January, 1905, he traveled several times to USA (there are 7 records for Alexander Rechnitzer in Ellis Island's passenger records until 1924, but it seems there were 2 persons with this name, because one of them arrived in November, 1924), where he lived in New York. In 1906 he was granted his first US patent (Nr. 809075). Rechnitzer must have been a brilliant engineer, but poor businessman and didn't manage to place his remarkable machines on the market. Financial conditions preyed on his mind to the extent that he became mentally unbalanced and died in despondency in April, 1922. His body was found in New York’s East River and finally found a resting place in the Potter's Field. But his life was not a failure, as his inventions have been widely commercialized by others.