Patent Model for an Adder with Carry Invented by George Farmer

Object Details

patentee

Farmer, George

Farmer, George

Description

This patent model for an adder has three concentric, linked discs that revolve on a central pivot. The bottom disc is numbered from 1 to 99 clockwise around its toothed edge, to represent hundreds and thousands. Above it is a smaller disc, also with teeth around the edge, numbered from 00 to 99 clockwise to represent units and tens. A window in the third, top, largest disc shows the result on the dials below. The largest disc is numbered from 1 to 100 around the edge. Atop this disc is a rotating arm. Moving the arm counterclockwise advances the inner disc proportionally, allowing one to enter numbers up to 99.

A lever extends from the side of the disc and bends over the top. If the arm rotates around a full 100 units, it pushes this lever, causing a carry. The lever also may be used to zero the hundreds and thousands digits. See U.S. patent 69,647 for “Improvement in Tallying Instrument.” According to the patent, the invention “relates to a new and improved method of registering or tallying the quantity of lumber measured, or keeping account of sums of money paid out or received . . .”

There was a George Farmer (born about 1831 in England, died 1880 in Saginaw, Michigan) who worked as a miller and shingle maker in Illinois and in Michigan. He is listed in the 1860 U.S. Census as living in Elmira in Stark County, Illinois, working as a miller. That same year he received a patent on August 21for an improvement in harvesters (#29685). By 1870, he was living in Saginaw, Michigan, still working as a miller. In the 1880 Census he is listed as a shingle manufacturer. He and his son, Albion, ran a shingle-making business in Saginaw under the name of George Farmer & Son. It is listed in the 1878 city directory for the town. The George Farmer who received the patent for this adder was a resident of Flint, which is near Saginaw.

Reference: George Farmer, “Improvement in Tallying Instrument,” U.S. Patent 69,647, granted October 8, 1867.

Location

Currently not on view

1867

ID Number

MA.252692

accession number

49064

catalog number

252692

Object Name

adder with carry

Object Type

Patent Model

Physical Description

brass (overall material)

Measurements

overall: 1.2 cm x 10.7 cm x 10.7 cm; 15/32 in x 4 7/32 in x 4 7/32 in

place made

United States: Michigan, Flint

place patented

United States: Michigan, Flint

See more items in

Medicine and Science: Mathematics

Adder

Science & Mathematics

National Museum of American History

subject

Mathematics

Record ID

nmah_690832

Metadata Usage (text)

CC0

GUID (Link to Original Record)

http://n2t.net/ark:/65665/ng49ca746a5-24e2-704b-e053-15f76fa0b4fa