Joseph Harris Jr. of Roxbury, Boston, Massachusetts, was a prolific inventor from the middle of XIX century. On 1 January 1861 he patented (US patent 31016) a simple adding device, somewhat similar to the earlier devices of Jabez Burns and John Ballou, and an inspiration for the later adding machine of Milton Jeffers.
The adding machine of Harris (see the lower patent drawing, unfortunately even the patent model didn’t survive to our time) consisted of series of revolving wheels provided with pins and spring escapements, acting together in connection with an inclined plane.
In order to avoid unnecessary prolixity, the patent drawing presents only three revolving wheels, designated for units (the right-hand wheel), tens (the middle) and hundreds (the left). The same arrangement may be extended to any number of wheels.
The wooden projections (marked with b, b, etc.), resembling cogs are intended only for turning the wheels, by placing the fore finger on them. The graduations of the indices of the wheels and dial are so made, that a projection corresponds with the figure immediately above.
The tens carry mechanism is implemented by means of the springs (marked with a, a, …), each placed half way in the interval between the 0 and 1 on the graduated index of wheels. When a spring comes in contact with an inclined plane (C), it is compressed so that instead of continuing to traverse a circumference outside the pins (n, n, …), it pushes a tens pin (n) one graduation ahead.
Biography of Joseph Harris
Little is known about the inventor—Joseph Harris Jr. from Boston, Mass. Joseph Eustis Harris was born on 31 Dec 1825 in Chelsea, Suffolk County, Massachusetts. He was the second son of Joseph Harris (1782–1864) and Mary Shillaber Harris (1785–1834). Joseph had four brothers (unfortunately three of them died in infancy)—William Harris (1823–1826), Giles David Shillaber Harris (1824–1826), William Giles Harris (1828–1897), and Daniel Shillaber Harris (1834–1835).
Joseph Eustis Harris was a holder of numerous patents for various devices, like: a gudgeon (US patent 5452 from 1848), mode of converting reciprocating into a rotary motion (US patent 7902 from 1850), driving circular saw (1853), lamp extinguisher (US patent 11524 from 1854), hand stamp (US patent 13308 from 1855), carpet cleaner (US patent 19465 from 1858), railway car (US patent 29882 from 1960), wheel for vehicles (US patent 272133 from 1883), tire heating furnace (US patent 350131 from 1886), car wheel (US patent 469919 from 1892), apparatus for heating tires (US patent 471704 from 1892), engine (US patent 474557 from 1892). Interestingly, a witness of Harris’ patent of adding machine was Otis Tufts Jr. (1839–1885), a son of the famous machinist and inventor Otis Tufts (1804–1869), who built printing machines, steam engines, firefighting equipment and invented the steam pile driver.
Joseph Eustis Harris died on 4 March 1899 (aged 73) in Revere, Suffolk County, Massachusetts.