George Jacobs and Ethel Mossman Jacobs: the enamel that made magnet wire

1901–1912 · THE PROBLEM TAKEN UP HERE, THE INDUSTRY FOUNDED HERE

The problem: Every electric motor, transformer and coil in the world is wound with magnet wire — copper or aluminum wire carrying its own insulation. At the turn of the century that insulation was cloth: bulky, short-lived, and the bottleneck of the electrical age. George Jacobs (1877–1945), a young chemist at General Electric's Fort Wayne Works in 1901, took up the problem of a chemical enamel that could be baked onto wire of any thickness, yet stay flexible enough to wind. The Fort Wayne telling, in Hawfield's News-Sentinel account of 13 December 1993, opens with the claim this entry exists to test: "Commercially useful magnet wire... was invented in Fort Wayne." The record underneath is a three-stage geography, and it is printed whole. Stage one is Fort Wayne: the problem and the first experiments were Jacobs's at the GE Works in 1901, where he also met Ethel Mossman, daughter of the hardware merchant William Mossman. Stage two is Cleveland: Jacobs moved there in 1905 for Sherwin-Williams, married Ethel in 1907 — she "helped him test various smelly solutions as possible magnet coatings" (Hawfield) — and the biographical summaries date his perfected formula to 1907, in Cleveland; Hawfield's telling instead has the perfection come after the return, at Dudlo in 1911, and both are carried. Stage three is Fort Wayne again, and it is the decisive one: William Mossman offered to finance the work if the couple returned; in 1911 William and B. Paul Mossman formed the Dudlo Wire Company here (Jacobs's biographical summaries put his 1911 start in Cleveland and the Fort Wayne factory in 1912 — the founding paperwork is carried as the two accounts give it), and the Wall Street factory opened in 1912 with a dozen employees. What Jacobs's process did, in Hawfield's summary, was coat wire of any thickness — "especially fine wire" — evenly with a baked chemical insulation that remained flexible; Dudlo's wire went into the ignition coils of the Model T, and by 1922 Dudlo was the largest manufacturer of magnet wire in the world. The industry then stayed where it was founded: Dudlo's alumni formed Rea Magnet Wire, Inca Manufacturing (later Phelps Dodge) and New Haven Wire, and the Fort Wayne companies descended from Jacobs's team have produced about two-thirds of the world's magnet wire ever since. Ethel Mossman Jacobs's place is stated exactly as the record gives it: a hands-on collaborator in the experiments, testing coatings beside her husband — no patent in her name was located, and none is claimed for her.

Sources:

1. Michael Hawfield, magnet-wire account, News-Sentinel, 13 December 1993 (egen.fortwayne.com) — the 1901 GE start, Ethel Mossman testing the solutions, the Mossman financing and Dudlo's 1911 formation, the process described, the two-thirds world share of the successor companies.
2. Wikipedia, "George Jacobs (inventor)" — 1877–1945; the 1905 Cleveland move, the formula perfected 1907, the 1911 business start, the Fort Wayne factory opened 1912, largest in the world by 1922.
3. History Center Notes & Queries, Tom Castaldi, "Magnet Wire Capital of the World" (10 October 2013), via ACGSI — Jacobs at the Fort Wayne Works in 1901, Dudlo and the successor companies.
4. Indianapolis Monthly, "How the World's First Home Gaming System Was Made in Indiana" — the 1911 breakthrough framing and Dudlo's founding on Wall Street.
5. Castle Gallery (Mossman house) account — the marriage, the financing condition, the Dudlo sale of 1927 and the alumni companies.