Instruments

1898 · Best.-Nr. 52564 — Denver CO: Wm. Ainsworth 2151 Lawrence St. 1898. Oblong 8vo. 24 pp. Text illustrations & diagrams throughout. Pink-coloured printed softcovers cover art of assayers scale on front and back covers minor shelfwear minor tidemark to upper fore-edges slight sunning still VG- copy w/ original printed mailing envelope addressed to Joe Seliger 1868-1947 former stenographer secretary and metalworker for Honeyman Hardware Co. Portland OR. First edition of this very rare catalogue detailing the precision balances for mineral assayers manufacturers chemists jewelers and pulp paper makers. Ainsworth 1850-1917 began as a fine watchmaker steam engineer toolmaker and distiller who moved to Denver in 1877 where he initially began working for A.B. Ingols Jewelry. By the 1880s he was operating a jewelry store repairing balance scales for miners and assayers because at the time these were produced in England and required months of turnaround time for them to be shipped back and repaired prior to Ainsworth. Ainsworth developed his own excellent balance as presented in this catalogue which featured a shortened balance beam speeding up the assaying process and were much preferred by Western assay offices and miners. He continued to operate as a watchmaker and clock repairer but by 1895 began producing Brunton’s newly patented Pocket Transit which together with the balances proved to be a very successful combination with his first Catalogues A & B depicting both products issued in 1898. The company would continue to grow after his death and would be purchased by Xavier Science Corporation and now owned by the Denver Instrument Company. No copies located in Worldcat; See: John Shannon & Geraldine Shannon The Assay Balance: Its Evolution and the History of the Companies That Made Them -- William Ainsworth Robert A. Paselk Scientific Instrument Museum Humboldt State Univ. Dept. of Chemistry 1999. Wm. Ainsworth, 2151 Lawrence St., paperback