Description
A rare opportunity to own the finest 6 inch doubly geared 360 degree circular protractor with magnifier, in keyhole (clam shell) shaped flame mahogany case measuring 7 x 7 x 1 inch. Signed in flowing script “Schmalcalder 82 Strand London”
All original bright golden lacquer, this instrument is not only unique, it is a 200 year old time capsule. Silvered scale (oxidised with time) with vernier, plotting wings with steel springs and pins, bronze center with cross hairs etched in glass, patented double pinion gears with bridge for rotation, this instrument is perfection understated.
Charles Augustus Schmalcalder was at this address from 1810-1828.
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Dealer information
ScientificaOpticae
Scientifica Opticae
Mark Hacking (Scientifica Opticae Inc.) has been an avid collector/dealer for over 30 years. A former Science teacher, he has an innate love for anything natural or mechanical. Specializing in optical (microscopes, telescopes), surveying, medical, weighing and drawing instruments, he is an active participant of the Scientific Instrument Fair in London. Living in Stratford, Ontario, Canada, with his wife and two children; Mark looks forward to meeting as many fellow collectors as possible, and has a worldwide following on eBay (Sciopti).