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Theronoid Electromagnetic Solenoid

The Theronoid is a clone of Gaylord Wilshire's equally famous "I-on-a-co" body coil. In 1928, the year following Wilshire's death, Philip Ilsey, manager of the Cleveland office of I-on-a-co, started his own company to produce the Theronoid. It consists of an 18 inch coil of several hundred feet of insulated wire covered with simulated leather, which gave rise to its nickname, the "magic horse collar". A nickel plated control box mounted on the belt has an on/off and a high/low toggle switch. In use, the coil was placed around the body and plugged into the house current for 3 to 5 ten minute treatments each day. It was claimed that all diseases could be cured by the Theronoid, and many testimonials were printed in the Theronoid Health News, covering virtually all maladies from constipation to paralysis. This tabloid was distributed by the various branch offices of the Theronoid Corp., each with its own testimonials, signed with local addresses.

An important accessory to the theronoid was a smaller coil wired to a flashlight bulb. When this coil was held near the theronoid, and parallel to the larger coil, the bulb would light. This simple demonstration of induction must have impressed those unfamiliar with the rudiments of electricity. That the Theronoid could cause a light bulb to glow that was not connected to anything was, for many, sufficient proof of its curative power, and made up for its shortcoming of having no moving parts, no tubes, and emitting no light or heat, or shocks.

The Theronoid Corp was investigated by the AMA, the Federal Trade Commission, and the Better Business Bureau. The Federal Radio Commission held a hearing on the Theronoid Corp's extensive radio advertising, and eventually, in 1933, the Federal Trade Commission banned advertising of the Theronoid as a therapeutic device.

Wilshire was hardly the first to use electromagnetism to cure disease, he was simply the first to exploit it successfully. His other claim to fame was as a land developer (Wilshire Blvd in Los Angeles). The grand daddy of all electromagnetic body coils was patented by Elias Smith, of Normal, Illinois, in 1869. He used a full body coil to induce magnetism in the patient. Since this was long before home electric plants, he used 3 or 4 Hill's batteries in the primary circuit to his helical coil and an interruptor to provide the "to and fro" ac current required to energize the secondary coil.

Smith's electromagnetic body coil patent illustration

Theronoid with test coil and original box for sale

Another pioneer in electromagnetic quackery was John McIntyre, of Jersey City, New Jersey. In 1905, long before Wilshire's I-on-a-co and Ilsey's Theronoid, McIntyre patented a coil quite similar to the magic horse collars appearing two decades later. He also encircled a vegetable garden with his electromagnetic apparatus. When a direct current source was used, he added a Rumkorff induction coil. When alternating current was used, his body coil was similar to the Theronoid.

The body coil

Treating a human being

Treating a horse

Treating vegetables

© 1998, American Artifacts, Taneytown, MD.
Contact: Richard Van Vleck