Electric Light Bulbs: What a Bright Idea

by Jim Woods

In 1879 when Thomas Edison demonstrated his light bulb, it set off a race by many manufacturers and inventors to cash in on the commercialization of electric lighting. Prior to this, there were electric arc lamps which produced an illuminating electric arc between two carbon rods. The disadvantage was the dirty carbon residue which limited its use to outdoors.

Several inventors came up with light bulbs prior to Edison but none were commercially viable until his carbonized cotton filament lamp. Actually two years prior to Edison's successful lamp, he had abandoned the light bulb after several thousand experiments. The limitation was the failure to produce an adequate vacuum to keep the filament from rapidly burning up. Then came the mercury vacuum pump and Edison resumed his quest producing the first viable commercial light bulb. In 1881 the first commercial installation occurred when 100 Edison wire terminal lamps were installed aboard the U.S.S. Columbia. This bulb had two wires coming out of the base which attached to screw terminals. Up until this time, the screw base had not been developed. The first screw base and socket made its appearance in 1882. Both were made of wood with a metal ring and contact on the lamp base.

Meanwhile, other manufacturers and inventors around the world developed improvements in the light bulb, plus a diversity of base and socket designs. There have been in excess of 25 base and socket designs available to the public. From the start, manufacturers infringed on the Edison patents and he quickly filed suit. The suits dragged on until 1892 when the court finally ruled in Edison's favor. Unfortunately, the original patents would run out in 1894. The rulings did, however, put many of the manufacturers out of business. The largest manufacturers to remain were Thomas Edison Co., Thomson-Houston Electric Co., and the Westinghouse Co.

By 1890 the Edison base accounted for about 70 percent of the bases made, Thomson-Houston bases about 15 percent and Westinghouse bases about 10 percent. The remaining 5 percent accounted for all the other base designs with several being quite rare. Edison didn't believe in alternating current, promoted the dangers of it, and wanted to limit its use to the electric chair. However, both Thomson-Houston and Westinghouse produced both alternating and direct current electrical equipment and accessories.

In 1892 Edison Co. became General Electric-Edison Co. and in 1894 merged with Thomson-Houston to become General Electric Co. In 1912 the National Electric Lamp Association was formed in Cleveland, Ohio which standardized lamp bases and sockets between all the manufacturers.

Any of the base designs could be licensed to a manufacturer and wasn't unusual for them to offer several different bases for their lamps to their distributors. I've seen Columbia Electric Lamps in at least three different bases­­ the Schaeffer, Edison, and Thomson-Houston.

The bulb designs and filaments varied widely. Early carbon filaments were made of carbonized cardboard, bristalboard, and cotton string. Next came carbonized bamboo and next asphalted carbonized bamboo. Next was carbonized squirted cellulose. Then there was high temperature carbonized cellulose known as the GEM filament. Produced for a short time were osmium and tantalum filaments. Next came non aligned tungsten and finally the drawn tungsten filament of today's incandescent lamp. The purpose was to develop more efficient filaments, which gave long life with more light for less watts.

Originally there were evacuation tips on top of the bulbs. It was very difficult to remove the air from the base of a bulb, although it could and was done for lamps requiring special optical characteristics, although they were comparatively expensive. Commercially tipped bulbs were no longer produced in 1923 when a cheaper base evacuation method was developed. A notable fact was the lead in wire in the glass tube between the base and filament were made of platinum.

An incandescent filament lamp of some interest is the Nernst glower. It was developed in Germany in 1900 and licensed to Westinghouse in 1903 for manufacture in the U.S. They made it from 1903 until 1912 when the more efficient drawn tungsten lamp became available. The glower looks more like a fixture than a bulb. There was a brass Edison screw base and housing which contained glass ballast tubes and a magnetic disconnect. At the bottom was a round globe held by a ventilated retaining ring. Inside the globe was a heater and filament block. The filament consisted of a strand of a coated cemented rarified earth surrounded with a heating coil made of platinum wire. The filament had to be heated before electricity would flow through it. The platinum coil provided the heat. When electricity began to flow through the filament, the magnetic disconnect removed the heating coil from the circuit and the ballast tubes provided a constant voltage through the filament. The Nernst glower was more efficient and provided good color for commercial use.

Collectors may specialize in collecting the different bases, the different filaments, the different lamp manufacturers or the various figural lamps. Figural lamps may be flame shaped, candle shaped, or the shapes of flowers, animals, Santa Clauses, inanimate objects, clowns, etc. Some collectors specialize in Christmas bulbs.

Pricing bulbs can be a very difficult proposition although a number of guides do list Christmas bulbs. The highest price paid that I am aware of is $6,850 for an Edison wood socket and wood-based bulb. There just aren't any price guides for early light bulbs and related equipment.

This is field for hard-core collectors if big dollars are involved. However, sometimes a really rare bulb can be purchased for a few dollars. The earliest bulbs used wood or composition materials for the insulator between the contacts. Next came plaster of paris and porcelain. The last still in use was a dark colored glass which made the scene about 1905. Bulbs with wood insulation start at about $300 and composition at about $125. Plaster of paris insulated bulbs start at about $60 and porcelain from between $15 to $20. Of course, rare lamps with no damage and full labels bring the highest prices. Broken filaments don't greatly impact prices of the earliest and rarest lamps but does make a big difference for later carbon and tungsten lamps.

This article cannot do justice to valuing light bulbs but should serve to educate readers a little about this obscure field of collecting. I would entertain inquiries of specific light bulb questions. Next month the discussion will be on auctions. If you have questions or suggestions, please send a note to Jim Woods, Zephyr, P.O. Box 1, Galesburg, IL 61402 or e-mail to zephyr@misslink.net.

Last Modified: July 11, 1996

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