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Winter 1995 | Volume 10 |  Issue 3

Ford’s Engines

HENRY FORD WAS INDEED A GREAT IN novator (“Henry Ford’s Big Flaw,” by John M. Staudenmaier, S.J.), but I question that those are “6000-horsepower gas-turbine engines in the powerhouse” shown on page 38 of the Fall 1994 issue. The prime movers driving the dynamos appear to be cross-compound Corliss steam engines. Gas turbines didn’t become available for industrial use until well after World War II.


The editors reply : The caption erred. The nine engines in the powerhouse were not gas turbines, which indeed did not yet exist in practical form, but combination gas-steam engines. Each unit consisted of a horizontal twin engine with tandem gas-engine cylinders on one side and tandem compound-steam cylinders on the other. The idea was to combine the economy and power of gas engines with the reliability and regularity of steam.

Forrest Gober
Austin, Tex.

Recorded History

YOUR ARTICLE “THE RACE TO VIDEO” (by Stewart Wolpin, Fall 1994) mentions that magnetic tape was developed in Germany during the Nazi era. The story is worth telling.

In the 1920s cigarettes were tipped with bronze to give them a golden look. The bronze powder stuck to a smoker’s lips. A consulting chemist, Dr. Fritz Pfleumer, worked on a way to prevent this by gluing the bronze particles to plastic that could be wrapped around the tips. As part of this work he hit on the idea of embedding iron filings in the tape, so the cigarettes could be scanned electronically to make sure they were all in the pack tips up.

As an opera fan, Pfleumer was unhappy with current recording technology, and it occurred to him that he could use the iron in his plastic tape as a recording medium. He sent his assistant, Heinz Thiele, to Berlin to help the AEG electrical company make it practical. Technical problems almost killed the project until Thiele, who happened to be a hunter, met Dr. Wilhelm Gaus, a leading chemist, on a hunting trip. Dr. Gaus suggested that the iron filings were too large to handle the small waves of high-frequency sound and that chemically grown iron oxide crystals could be made small enough. This worked.

Shortly thereafter one of the wax disks containing a speech by Reichsmarschall Hermann Goering was broken just before it was to be broadcast. When the head of the network was hauled before Goering the next day, he saved himself by saying that the newly developed tape machines would prevent such mishaps in the future. Goering was so impressed that he soon had all German radio stations equipped with tape recorders.

Nicholas W. Beeson
Boston, Mass.

Recorded History

THE STORY OF HOW AUDIOTAPE WAS invented in Germany in 1935 and preserved as a well-kept military secret reminds me of a World War II episode in which the Allies captured intact a German U-boat. Military intelligence personnel swarmed over the craft and stripped it down. Even the fuses in the electrical systems were disassembled and examined for the stories they might tell.

Disassembly of the fuses revealed that some fuse links were made of solid silver. This was interpreted to mean that the German manufacturing effort was sorely lacking in zinc. Not until after the war was it learned that the Germans had invented the current-limiting fuse—a fuse that cleared a fault current before the fault-current wave could crest on its first half-cycle, thereby greatly limiting damage.

Ed Palko
North Barrington, Ill.

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