Antique 6-Inch Parallel Rule in Ebony & Brass c. 1880–1900 | English Drafting Instrument

For the draftsman …  an antique English parallel rule in ebony and brass, dating to around 1880-1900, with two finely finished ebony bars joined by shaped brass links. At six inches in length, it was likely intended for a fitted mathematical or drawing-instrument case rather than for use with larger plans or charts.  In excellent condition, it would make a distinctive display on a gentleman’s desk or library shelf.

Parallel rules were standard working instruments for 19th-century draftsmen, engineers, surveyors, mapmakers, and navigators. By opening and “walking” the linked bars across a page, the user could preserve an exact angle, draw parallel construction lines, and transfer bearings between a plotted course and the compass rose on a chart. Six-inch examples were typically intended for portable sets, where compactness mattered more than the reach required for larger architectural plans or Admiralty charts.

Dimensions (closed): 6” x 1-3/8” x 1/16”
Weight: 0.8 oz.

Condition notes: Excellent antique condition overall with ebony bars straight, smooth, and evenly toned, showing only very minor surface wear from age and handling. Shaped brass links show some tarnish but no visible cracks, breaks, or replaced hardware. Mechanism opens and closes smoothly and remains securely assembled. Very small nicks and chips are present at each end, visible only on close inspection and not affecting structure or display. No warping or other significant damage noted. Other items in photos not included.

All items are hand-wrapped and packed with care for secure delivery.  We offer flat rate shipping via USPS Ground Advantage for $10, or USPS Priority Mail for $15. Orders over $100 (not including taxes) ship free via USPS Priority Mail — any shipping charges for orders over $100 will be refunded after checkout. We pack using recycled and recyclable materials whenever possible.

Sorry, no returns or cancellations.  Please view all photos for more detail and feel free to contact the shop with any questions prior to purchase.