Balances and Scales

Ainsworth Assay Balance Marking | AINSWORTH ASSAY BALANCE - Wm. Ainsworth assay button balance, serial #643, made about 1892, case is French polished mahogany from Gold Coast of Africa with two front drawers with ivory pulls, all brass hardware, button pans are German silver, counter balance sliding door with original lock and key, measures 20 in. wide, 10 in. deep and 16 in. high, 8 in. beam, marked Wm. AINSWORTH MAKER; 643; DENVER, COLO with two bubble levels, early balance made by Ainsworth prior to company name change to Ainsworth and Sons in 1899, unknown model number since it was made before first Ainsworth catalog in 1895, appears to be early version of No. 045 Silver Button Balance advertised in 1903 Henry Heil Chemical Company St. Louis, Mo. catalog (item #2601/20). [While several types of balances were used in the fire-assaying process (see pulp balances elsewhere in my pics), the assay or button balance (terms are synonymous) is unique. Its only purpose was to weigh the button or small pellet of gold or silver which was the final result of the assaying process. The assay balance was designed to be very accurate with sensitivities of 0.01 to 0.02 milligrams. Although the internal workings of an assay balance and a pulp or analytical balance are different, the easiest way to tell them apart is the size of the pans. Assay balance pans vary from 1/4 to 5/8 in. in diameter while the pulp balance has 2 in. diameter pans or larger. The history of assay balance manufacturing in the western US begins with William Ainsworth, America’s premiere assay balance and analytical balance maker. Ainsworth was born January 22, 1850 in Lancashire, England. He, his mother and a sister Anne Elizabeth (born May 1842) came to America in 1853. In his teens, he obtained a job in the Elgin watch factory at Elgin, Illinois where his duties consisted of selecting, testing, installing and manipulating the hair springs of the watches, a very delicate and tedious job. He later worked for the Union Copper Distilling Company of Calumet in Cook County, Illinois where he was employed as a steam engineer and eventually Chief Engineer. In 1874, he moved to Black River Falls, Wisconsin, where he worked for J. W. Cole and Company as a watch maker. There he met and married Elma E. Eastman. It is evident through his work experiences that Ainsworth learned to be top-notch toolmaker and mechanical engineer. In 1875, the young couple moved west, traveled through Denver and settled in Central City, Colorado, where he turned to his watch making trade to earn a living, working for various jewelers there. This work led Ainsworth into contact with a variety of people, mostly miners and assayers, and it is believed that these associations eventually led him into the balance business. To help the assayers, he began repairing assay balances and in time learned the "secrets of the trade." In 1877 the Ainsworths moved to Denver. Although his primary sources of income were watch making, machining and time lock repairing for banks, he continued to develop his balance trade on the side. The Denver City Directory of 1879 lists William Ainsworth as a watch maker for A. B. Ingols Jewelry and in 1880 and 1881 he is listed as an owner in the Swain & Ainsworth Machine Shop on 474 Larimer Street. It was in 1879 while serving as a watch maker for A. B. Ingols that Ainsworth probably made his first balance. He began by buying a small hand planer and on this planer he machined the bed of a small engine lathe. He built the lathe in its entirety and then began the slow process of making his own taps and dies. He established his own standards of sizes and thread forms. It is also believed that he then constructed a milling machine. The first balance parts were turned out on the small lathe and miller with a great deal of hand work. The brass beams were laid out and sawed with a jeweler's saw and the balance cases were made of high grade African mahogany with a French polish finish. In 1882 Ainsworth had his watch making and balance shop at 248 16th Street and several years later he located his shop at 577 and 579 Lawrence St. This address eventually became his factory and home for many years. In 1887 a street re-numbering occurred and, although the factory and home remained in the same building at the same location, the address became 2151 Lawrence. Information regarding Ainsworth's early balances is, of course, quite scarce. A serial number record from #473 to #2027 is known, but it only provides a description; there are no dates. It is possible to date balance serial #1000 at 1898, which would mean that Ainsworth built one thousand balances between 1880 and 1898, or approximately 55 balances a year. Since in 1899 the company built approximately 100 balances, 55 a year does not seem unlikely. One of Ainsworth's outstanding contributions to the industry was his development of shortening the balance beam, which effectively quickened the assaying process. The firm of William Ainsworth Balance Company started in 1880 even though he continued with his watch repair and time lock service. Ainsworth balances were almost immediately preferred by the local assayers. In spite of this acceptance, however, the problem of building sufficient volume to support a family with this infant industry was a tough one and Ainsworth found it necessary to hire out his services to keep the business going. It may be this situation that caused him to be listed as a watch maker and machinist rather than a balance maker. William Ainsworth provided the experience and perhaps the motivation for a number of prospective balance manufacturers. Of the five prominent western balance companies, all but one of the owners had at least some part of their training with William Ainsworth. They were Elmer Smith and Fred Thompson who would establish Smith & Thompson Balance Company (later to become the Thompson Balance Company), Albert Dahlberg and Hugo Franow who would establish the Denver Balance Company, and George Keller who would establish the Keller Balance Company in Salt Lake City. The latter gave some training and opportunity to George Spiegel and Wilfred Huesser in their balance making endeavors. The Ainsworth Balance Company continued to prosper and around 1895, Mr. D. W. Brunton brought his newly patented Brunton Pocket Transit to William Ainsworth to manufacture. The first lot consisted of twenty-five instruments, and thus began the Brunton Pocket Transit business, which was to serve the company well into the 20th century. Around 1899, William's two sons joined him and the company became known as Ainsworth and Sons. Robert G. Ainsworth was born in Pennsylvania on January 1, 1878 and Alfred W. Ainsworth on October 30, 1884. Both got their early training in the Ainsworth factory and it was a natural course of events that led them to join the firm in 1899. The success of the Brunton Pocket Transit may have contributed to the decision of Ainsworth and Sons Company to build and market surveying instruments. In any event, the work was started on surveying instruments around 1904, but the first transits were not marketed until 1906. This continued until 1940, when the transit business was sold to Harry Glantz, who had been an instrument maker for Ainsworth. After that purchase, the transit business that had operated under the Ainsworth name became known as Rocky Mountain Instrument Company. Sometime around 1910, Ainsworth & Sons began a major shift from manufacturing assay balances to manufacturing analytical balances. William Ainsworth died January 1, 1917, leaving the management of the company in the hands of his two sons and his wife, Elma E. Ainsworth. From shortly before WW I until the 1930s the company went through a period of wide diversification. These included manufacture of a Dodge automobile transmission, spotlights, tire gauges, automobile signaling devices, perfume atomizers, toilet flush valves, moving picture machines, smoking pipes, furnace grates, valve-facing tools for automobiles, seismographs, mining carbide lamps, gunsights, and radio parts. Ainsworth and Sons were the sole manufacturers of the hard to find Arnold Carbide Candle (shown in my carbide hand lamp pics) patented by Ralph R. Arnold of Cripple Creek, CO in 1912. By 1934 the idea of wooden cased balances was abandoned and the Company began producing balances in metal cases. The Ainsworth and Sons Company was purchased in 1965 by Xavier Science Corporation, and in 1967 the plant was moved to the Denver Tech Center. During this time, ownership of the company went through several hands, including Tastee-Freeze Industries, Inc. of Chicago. More recently, the rights to the Ainsworth name have been purchased by the Denver Instrument Company of Denver. See John and Geraldine Shannon, The Assay Balance Its Evolution and the Histories of the Companies That Made Them, 1999 and John Shannon, Mining Artifact Collector #2, pp 30-31]

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