Cobalt Blue Ink Bottle Marked “POLYGON”

Description

The bottle is made of deep cobalt blue glass, featuring a distinctive square base with a “geometric” or “polygon” faceted top.

• Design: The top surface is molded with a deep diagonal groove that serves as a pen channel, allowing a dip pen to be laid across the bottle without staining the desk.
• Markings: The word “POLYGON” is embossed in a circular fashion around the offset neck.
• Manufacturing: The presence of visible mold seams and the slightly crude finish of the sheared or “tooled” lip suggest a production date between 1890 and 1910.

The Registration Number

On the base of the bottle, there is an embossed registration number. While it is weathered, it appears to be: REGd NO 333008

Registration Details

According to the British Board of Trade design records:

• Registration Date: This number was registered in 1899.
• Registered By: It was typically associated with M. Lindner (a London-based stationer) or manufactured for them by a major glassworks like Pillsbury & Co.
• Purpose: The registration was for the specific “Polygon” shape and the functional diagonal pen-rest feature.

History of Polygon Ink

The “Polygon” brand was a successful line of writing inks during the transition from the 19th to the 20th century.

1. Innovation in Stationery: Before the fountain pen became ubiquitous, desk bottles like this were essential. The “Polygon” bottle was marketed as a superior design because its heavy, low-profile base made it difficult to tip over, and the built-in pen rest was a convenient “all-in-one” solution for the writer.
2. Lindner of London: This firm was a prominent distributor of “office sundries.” They marketed Polygon ink as a premium product, often sold in these rich cobalt blue bottles to protect the chemical stability of the ink from light, though the color was also a major selling point for decorative desk sets.
3. Variations: While this square version is classic, the “Polygon” line included several shapes (including actual hexagonal and octagonal versions) and colors, though cobalt blue remains the most iconic and collectible.