The American businessman Gilbert Warren Chapin was a holder of three quite interesting patents for calculating machines—US patent №99533 and US patent №106999 from 1870, and US patent №646599 from 1900. The first and third patents are for key-operated adding devices, while the second is for a small adder with manually rotating numeral wheels. We know that in 1869 Chapin began to work at the financial department of the largest shoe jobbing concern in New York, keeping this position for 17 years, and later he worked as a bank actuary, so he definitely needed a calculating tool in his daily work.
At this time, there were quite a few key-operated calculating machines, invented in Europe (e.g. machines of James White, Luigi Torchi, and Jean-Baptiste Schwilgué), but there are also a number of patents issued in the United States on machines of this class, let’s mention only the devices of Dubois Parmelee from 1850, Thomas Hill from 1857, Leonard Nutz from 1858 and Caroline Winter from 1859. The first (and still more the third) adding device of Chapin had better construction compared to all of them, although not resolve a common problem for the early key-driven calculators—overthrowing the numeral wheels under a quick keystroke.
The first adding machine of Chapin
Let’s examine the first adding machine of Gilbert Chapin (patent application filled in July 1869, patent granted in February 1870), using the patent drawings (see the lower images).
The machine was designed to add two columns of digits at a time and with an attempt to provide means to shift the accumulator mechanism, or the numeral wheels and carry-transfer devices, so that columns of items having four places could be added by such a shift.
In Fig. 1 there are four wheels marked with V. These wheels, although showing no numerals, are, according to the specification, the numeral wheels of the machine.
The wheels are provided with a one-step ratchet device for transferring the tens, consisting of the spring frame and pawl shown in Fig. 3, which is operated by a pin in the lower wheel.
In Figure 1 the units and tens wheels are shown meshed with their driving gears. These gears are not numbered but are said to be fast to the shafts N and M, respectively (see Fig. 2).
Fast on the shaft M, is a series of nine ratchet-toothed gears (marked O), and a like series of gears P, are fast to the shaft N. Coacting with each of these ratchet-toothed gears is a ratchet-toothed rack F, pivoted at its lower end to a key lever H, and pressed forward into engagement with its ratchet gear by a spring G.
The key levers H, of which there are two sets, one set with the finger-pieces K and the other with the finger-piece J, are all pivoted on the block I, and held depressed at the rear by an elastic band L. The two sets of racks F, are each provided with a number of teeth arranged progressively from 1 to 9, the rack connected with the Nr. 1 key having 1 ratchet tooth, the Nr. 2 having 2 teeth, etc.
By this arrangement, the inventor expected to add the units and tens of a column of numerical items, and then by shifting the numeral wheels and their transfer devices, which are mounted on a frame, designed for this purpose, he expected to add up the hundreds and thousands of the same column of items.
The machine of Chapin, just like the similar machines of Parmelee and Hill, was made without a thought as to what would happen when a key was depressed with a quick stroke, as there was no provision for control of the numeral wheels against overthrow.
It is hardly conceivable that Chapin should have overlooked the necessity of gauging the throw of the racks F, but such is the fact, as no provision of such means is provided in the drawing, and neither was mentioned in the specification. Even a single tooth of the rack F, could, under a quick keystroke, overthrow the numeral wheels, and the same is true for the carry transfer mechanism.
The second adding machine of Chapin
The second adding machine of Chapin (patented in September 1870) is a much smaller and simpler device (see the patent drawing below) with manually rotating numeral wheels, similar to the earlier Addometer of Jabez Burns and Calculator of John Ballou.
According to the specification, this simple adding device has a simple, but reliable construction, missing the above-mentioned problem of the early key-driven calculators—overthrowing the numeral wheels under a quick keystroke, paying for this with its slower operation. Dimensions of the device are 20x15x15 cm, and capacity is 7 numeral wheels.
It seems at least several devices of this type (see the upper photo) have been manufactured by Gilbert Chapin.
The third adding machine of Chapin
The third adding machine of Chapin, patented in April 1900 (see the nearby patent drawing), was again a key-operated adder, this time with a portable and reliable construction (see the nearby patent drawing). Unfortunately, despite its sound design, it remained unnoticed in the world of mechanical calculators and no working model survived.
Chapin obviously noticed the main flaw of his first adding machine—no provision for control of the numeral wheels against overthrow, so he decided to address this flaw in the construction of his last calculator, stating:
In many of the devices of the prior art, the mechanism for transmitting the proper movements from the keys of the keyboard to the registering-dials is so complicated and so sensitive that in ordinary usage the machines soon become inaccurate, the registering-dials moving too far or too little to bring the character into proper position.
The object of my invention is to produce a device of this class in which many of the objectionable features tending to inaccuracy are eliminated, at the same time providing a machine simple in construction and operation and one which will operate positively, rapidly, and accurately; further, to provide mechanism by which the registering-dials will always be brought to a fixed and positive stop, allowing a substantially-uniform amount of depression to each of the several keys of the keyboard.
Biography of Gilbert Chapin
Gilbert Warren Chapin was born on 1 August 1847, in Springfield, Mass., to the typical New England Yankees Joel Chapin and Amelia Parsons. Joel Chapin (1815-1852), born on 16 August 1815, in Enfield, Conn., was the seventh generation heir of the glorious Samuel Chapin (1598–1675)—a prominent early settler, selectman, magistrate, and deacon of Springfield, Mass. (Actor Clint Eastwood is also a direct descendant of Deacon Samuel Chapin).
Joel Chapin was brought up on his family farm (he was the sixth son of Timothy and his second wife Susanna (Terry) Chapin) and received a good education in public schools and at Yale College. He was a ripe scholar, a good linguist, spoke several languages, author of a series of four grammars, and held a high place as an educator. He was the principal of Boys’ Schools in Springfield, Mass., Bridgeport, Trumbull, and other places in Connecticut. He studied for the ministry and was licensed to preach shortly before his early death on 27 August 1852, in Bridgeport.
Joel Chapin married Amelia Parsons (born 1 May 1818 in Enfield–died 22 Dec. 1882 in Brooklyn), daughter of Elisha (a farmer and leading citizen of town and church in Enfield, Connecticut) and Lovisa (Gleason) Parsons, on 1 September 1841, in Enfield. They had three sons: John Elliot (13 July 1842-3 May 1924), Joel Leander (30 Dec. 1843-20 July 1864, a remarkable boy, who volunteered during the Civil War and died only 20 y.o. as a prisoner of war), and Gilbert Warren.
Gilbert Warren received his education in the common schools and worked on the farm in his boyhood. When he was 18 years old he left home and began his business career as a clerk in a wholesale carpet establishment. Soon after he took a position clerk in a retail store carpet store and at the end of his third year in business accepted a position in the financial department of the largest shoe jobbing concern in Brooklyn, New York. Altogether he spent 17 years in the shoe business. He also gained some experience in the newspaper and insurance business.
Since 1889 Chapin has been in the Society for Savings of Hartford (the largest bank in New England) where his brother served as treasurer, and for many years has been its actuary and was in charge of the securities and accounts of the bank, representing various interests in the capacity of executor, conservator, trustee, etc.
Later Gilbert Chapin developed a real estate and rental business in Hartford and became a member of many societies and clubs.
Gilbert Chapin married on 22 October 1874, at Mansfield Center, Conn., to Delia Persis Campbell (4 Feb. 1849–31 Jan. 1902), his distant cousin and daughter of Herbert Barrows (a New York merchant) and Cynthia Selima (Storrs) Campbell (Storrs was a prominent Mansfield family, related to Chapin family). They had a child—Warren Storrs Chapin (see the nearby photo), born on 4 July 1885 in Brooklyn, New York (died 11 Feb. 1954). Delia passed away on 31 Jan. 1902 in Hartford, Conn. Later on 17 November 1909, Gilbert Chapin married Lucy Gould Stock (b. 9 Feb. 1873), the daughter of Thomas H. (1834-1903) and Louise M. (Griffin) Stock (1842-1900) from Springfield, Mass.
Besides the above-mentioned three patents for calculating machines, Gilbert Chapin is also a holder of two other patents—for bird-cage screen and for coupon cutter (pat. Nr. 454850).
Gilbert Warren Chapin died on 1 April 1932, in Hartford and was buried in Mansfield Center Cemetery, Conn., near his wife Delia.