The Talking Machine Forum — For All Antique Phonographs & Recordings

I was wondering why the Edison 2 minutes from numbers somewhere in the 9200's to the late 9400's have no ribs inside,but have smooth insides?edisonplayer

Like so many other things in the phonograph world, it was because of a lawsuit over patent rights. Once the patent expired, the ribs came back. I don't recall who sued Edison over this - perhaps someone else can fill in the details?

The temporary dropping of concentric or spiral ribs from the Edison cylinders was a result of litigation pushed by James Andem, a former personal friend of Thomas Edison, and once the president of the Ohio Phonograph Company during the old North American Phonograph Co. days. In 1905, Andem, by then secretary of the New York Phonograph Company, instituted lawsuits to deprive the Edison companies of the use of certain items patented in the late 1880s and early 1890s. Among these were the interior cylinder ribs, mica diaphragms, and the ball catch endgate lock. The litigation was eventually successful, and this explains the appearance of smooth cylinder interiors (for a short time), copper diaphragms, and the Aiken-designed endgate lock used on the Home, Triumph, and their derivatives.

George P.