Evershed & Vignoles c.1910s Megger Direct Reading Resistance Box

Beautiful dove-tailed antique wooden box electrical test instrument, an early Evershed & Vignoles Direct Reading Resistance Box (to be used with the company’s separate “megger” box, or as a standalone decade resistance box). The top-deck is a finely engraved brass plate, there are four Bakelite knobs, labeled: Thousands, Hundreds, Tens, Units.

Made circa 1910s (this date is based upon a 1925 Guest-i-mate of a later design shown at radiomuseum.org, and, not much earlier than 1910 since Bakelite — the world’s first synthetic plastic — was introduced in 1907. Tested with a DMM and determined functional, all resistances up to the maximum 9999 ohms are working.

The nameplate on top reads: Evershed’s Patent, Direct Reading Resistance Box, No. 38814, Maximum 9999 Ohms, Evershed & Vignoles Ltd, London. On the front is a small brass plaque attached by a previous owner, it reads: P.S.C.T. S1929

Inside is large, thick paper label with instructions for use, its title reads: EVERSHED’S PATENT BRIDGE-MEGGER and DIRECT READING READING RESISTANCE BOX. The company address at lower-right: Acton Lane Works, Chiswick, LONDON, W.

A pair of original test leads attach to thumbscrew terminals labeled “R”. It is missing its original leather strap-type handle, which was slotted and designed for easy removal/replacement.

The wooden box measures about 13 x 6 inches by 5.5 inches tall (to the top of handle-mount studs), weight is 8 lbs 10 oz.

A fine early 20th century electronic test instrument and nice addition to your collection of antique engineering tools, or for the electrical engineer in your life, or your friend’s cool steampunk collection.

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REFERENCES

In 1889, Sydney Evershed invented the insulation tester, and in 1903 registered the trademark “Megger”, a bit more at the present-day company’s About Megger

A later model Evershed box shown at radiomuseum.org with a Guest-i-mate date of 1925.