# Dubois D. Parmelee

Каждый мечтает изменить мир, но никто не ставит целью изменить самого себя.
Лев Николаевич Толстой

In 1850 Dubois D. Parmelee, a 20-year-old student at New Paltz Academy (later the State University of New York), patented a calculator, which seems to be the fourth key-driven adding machine in the world (after the machines of James White, Luigi Torchi, and Jean-Baptiste Schwilgué), thus putting the foundation of the US key-driven calculating machines industry, which will become the leading in the world industry some 40 years later.

Parmelee was an inventive young man, who devised his Machine for Making Calculations in Figures while in the New Paltz Academy, driven probably by the need to facilitate the tedious mathematical calculations. Unfortunately, nothing except the patent application survived to the present, even the patent model was lost (for most of the 19th century, US Patent Office required inventors to submit a model with their patent applications. Inventors placed great importance on their models and viewed a well-executed model as the key element in obtaining a patent.)

Like other machines of this kind (so-called single-column adders), the device of Parmelee was intended to add a single digit at a time, i.e. the unit column is entered first, then the tens, the hundreds, the thousands, and so on, certainly rather cumbersome task (as every partial sum had to be recorded on paper and the sum eventually performed), which greatly limits the usefulness of such devices.

The calculator of Parmelee is a simple apparatus for making additions of long columns of figures by means of a movable index or register acted upon by keys of a fingerboard (keyboard). The device (see the lower patent drawing from US patent 7074) has nine keys, which are numbered from 1 to 9 and have increasing heights.

The motion from the keys is transferred to the stick (graduated rule) B in the back part. This stick has in his front part teeth, which are engaging with the two tongues m and k (see figure 2 from the patent drawing). The sidebar of the stick is graduated and numbered in such a way, that one tooth corresponds to one division. On pressing a key, lever E will raise the tongue k to so many divisions, according to the digit, written on the key. Then the lever will be returned to the starting position by means of the spring n. When entering the numbers (or when the stick will be raised to the uppermost position), the operator can see the number in the sidebar, and then pulls by means of the two ropes p the two tongues and the stick will fall down through the box to its stop ready to be again raised.

It seems that if the machine of Parmelee was ever used to add with, the operator would have to use a pussyfoot keystroke, otherwise, the numeral bar would overshoot and give a wrong result, as no provision was made to overcome the momentum, that could be given the numeral bar in an adding action.

In his patent description, Parmelee proposed some improvements, as the most important one was to improve the visualization, including in the construction gear wheels and strips.

In August 1850 the calculator of Parmelee was presented in the American popular science magazine Scientific American (see the image below):

#### Biography of Dubois D. Parmelee

Dubois (Du Bois) Duncombe Parmelee, a known at his time chemist and inventor, was born on 15 August 1829, in Redding, a small town in Fairfield County, Connecticut. He was the son of Ezra Parmelee and Mary Duncombe Parmelee. Ezra Parmelee (born 5 March 1796) descended from one of the area’s first colonial settlers, John Parmelee (1613-1684) from East Sussex, England, who arrived at New Haven in July 1639.

After attending a private school in Boston, Parmelee enrolled in New Paltz Academy (now the State University of New York at New Paltz), where he received in the second half of the 1850s a degree in medicine and chemistry. He never worked as a physician however but devoted his life primarily to experimental chemistry.

After his graduation, Parmelee worked in the rubber industry in Salem, Mass, (in the US Census 1860 records he is listed as Dubois D. Parmalee, chemist, 29 y.o., living in 2nd Ward of Salem) where he invented the cold process of manufacturing rubber and had a rubber business until the Goodyear invention ran out and rubber prices dropped. Around 1861 he settled in New York and was listed in the New York City directories of the period 1 May 1862, through 1 May 1873, as a chemist. Later Parmelee worked for New York Belting and Packing Co. as a consulting chemist and took part in producing the first aluminum in the USA.

Parmelee was one of the most active members of the American Institute of the City of New York and several exhibits of his inventions have been made there. He joined the American Institute in 1861, and he was listed as an annual member in the membership list of 1868, with his profession given as Practical Chemist.

Parmelee was a holder of quite a few patents, primarily in the fields of rubber manufacturing and implementation (pat. №№ US24401, US26551, US48993, US48993, US187302, US146092, etc.) It seems his most important invention was the suction socket for artificial limbs (U.S. Utility Patent №37637), some 80 years before it received general acceptance. Parmelee fastened a body socket to the limb with atmospheric pressure, thus being the first inventor to do so with satisfactory results.

Dubois Parmelee married Rosina (Benisia) Gloward (b. 1836) in New York City on 7 October 1857, but apparently, they had no children.

Dubois Duncombe Parmelee died of heart failure on 15 April 1897, in New York.