Linderoos Adding Machine

This shield-shaped brass instrument has an inset rotating disc with 100 holes numbered clockwise around the edge. The outside of the disc also has 100 numbered divisions. A piece of the outer shield curves in across the disc to the center and serves as a stop in addition. Above the disc are three smaller wheels on top of the shield. The wheel on the right is numbered counterclockwise from 0 to 9 and labeled: 100 1000. The wheel in the middle is numbered clockwise from 0 to 9 and labeled: 1000 10,000. The leftmost wheel is numbered clockwise by tens from 0 to ten and labeled: 10,000 100,000. There is a pointer for each wheel. Rotating the large disc through 100 causes the “100 1000” disc to rotate one unit (as presently arranged, the reading on the wheel decreases by one unit). The small wheels also may be rotated separately, although the carry to higher places does not seem to work properly.

Linderoos, a native of Scandinavia, emigrated to California and, by 1867, was an attorney and notary public in Point Arena (the town was also known as Punta Arena). In1881, he would be appointed a Postmaster there. He died in 1885.

References:

Gustavus Linderoos, “Improvement in Adding-Machines,” U.S. Patent No. 140,146, June 24, 1873. Here he is listed as a resident of Point Arena, California.

Ancestry.com.

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