The Addition Machine of John T. Campbell

In 1859 the young carpenter from Rockville, Indiana, John Campbell, patented a 5-positional adding device (called Addition Machine), similar to these of the French Jean Lépine and Hillerin de Boistissandeau from 1725.

John Tenbrook Campbell was born in 1833 in a farm near Montezuma, Parke County, Indiana, in the family of Joseph Campbell (1808-1843) and Rachel Tenbrook Campbell (1814-1843).

John was one of 7 children and spent his boyhood days in his father's mills (Rockport Mills). He had a hard time after the early death of his parents, and at 15, he left home and secured employment on a farm, where he remained until he was 17. Then he began as a carpenter, also studying at Annapolis and Western Manual Labor School. For 10 ensuing years he worked at his trade of a carpenter during the summer and followed the profession of a teacher in the winter season, meantime spending another term at the Labor School.

It was during this period, when he patented his adding device (US patent 24990), shown in the picture bellow.

The calculating machine of John T. Campbell, the patent drawing

It was a simple adding device, which internal mechanism is rather similar to the devices of Lépine and Boistissandeau, although Campbell most probably was not aware of the abovementioned and has devised the mechanism himself.

John Campbell took part in the Civil War, was wounded and returned home in 1862. After the war he was appointed on several public duties, e.g. Assistant Provost Marshall, Treasurer of Parke County, Assistant Assessor of Internal Revenue, Assistant of the Indiana Bureau of Statistics and Geology, etc. In 1870s he opened a hotel, but failing to make a success of the enterprise went out of business.

Campbell was so constituted mentally that he cannot learn anything until he becomes interested in it, but then only with great difficulty can he be prevented from learning it. He rummaged libraries, seeking every source of information and mastering the subject in a very short time. When the inventive fever was on, his most important business must stand aside until he solves the problem, whatever it may be, that has presented itself to his mind.

John Campbell published various books and articles in the fields of statistics, geology, labor problems, etc., and devised several other devices, e.g. a device for ascertaining the distance, methods of measuring the height of the clouds. He had been granted letters patents upon several inventions, the principal of which is a surveyor's transit. In 1870s he matured a road system in statutory form for creating, constructing, repairing and maintaining the public highways, on which he took out a copyright.