Description

JENKIN’S “PATENT MAGNETIC COMPASS BEARING PROTRACTOR AND COMPASS COURSE FINDER,” English, late 19th century, unsigned. Made of plated brass with an 11-1/2″ (29 cm) long clampable brass index arm, this multipurpose navigational charting instrument has a divided square and calibrated clampable circle with compass headings and degree scale. We have seen an original instructional sheet and testimonials, indicating that the principal advantage of this instrument to the navigator is the ability to apply the compass error (variation and deviation combined) to “any Bearings he may wish to take before they are actually taken, and this entirely does away with the chance of applying the Error the wrong way, a not uncommon mistake.” A most uncommon instrument, very fine, with the original mahogany box.