Dating keuffel drafting tools
This unit features the ability to take reading areas in square inches or square centimeters. It also produces measurements in both the English and Metric systems.
It also features the original case and cardboard outer box. There's no bargain in buying an instrument that will only read out metric measurements if you are working with boat plans in English measurements. Get the newest, cleanest looking instrument you can find.
Also included is a K&E Instruction Manual which describes basic theory of polar planimeter use and detailed instruction. Compare photos of the same model, as above, and make sure all the parts of the instrument are there.
Keuffel Bergenau (1872-1960), William Gottfried (“Willy G.”) Keuffel (1875-1942), Martha Keuffel (1876-79), Ottilie Keuffel Busch (1880-1971), Margarethe Bertha (“Gretchen”) Keuffel Keller (1885-1974), and Hermann Keuffel (1886-87). Wilhelm Keuffel died on October 1, 1908, at his home in Hoboken at the age of seventy. Keuffel’s partner, Hermann Esser, was born on December 30, 1845, in Elberfeld, in the Rhineland province of the Kingdom of Prussia. Matthew’s Lutheran Church in Hoboken; the couple had two children: Otto Esser (born 1870) and Klara Esser (born 1875). Esser retired from K&E in 1902, at which point he sold his share of the business to Keuffel.
He returned to Germany that spring and died in Bad Godesberg am Rhein on April 16, 1908, at the age of sixty-two. According to Keuffel family lore, Keuffel and Esser first met in Hanover, where both had worked for the Ravené Company, a Berlin-based iron manufacturer. After arriving in New York, however, Keuffel decided to part with the Ravené Company and go into business for himself, and he encouraged his former co-worker to immigrate and partner with him. Esser arrived within a matter of months.
"Keuffel & Esser 620015 KE Compensating Polar Planimeter A precision tool for measuring areas of both regular and irregular shape from maps, plans, blueprints, photographs, and other documents.
Simply trace the outline of an area with the cursor to obtain its size.
They show up on ebay regularly, but caveat-whatever. I randomly go trolling for an integrating planimeter to do center of buoyancy calculations, but have yet to find one for less than 0. If you watch flea Bay, you should be able to pick up a Keuffel and Esser Model 620015 for somewhere between and .