Berliner Gramophone formulations remained the standard disc record material until the first vinyl records – initially made only for radio use and other special applications – were introduced in the 1930s. Beginning in 1896, Berliner's gramophones were made by Philadelphia-based machinist Eldridge Johnson, who added a spring motor to drive the previously hand-rotated turntable. Berliner also opened an office in New York City, staffed by Frank Seaman and O. D. LaDow and organized as the National Gramophone Company. Master recordings were made onto zinc plates, which were then electroplated and a negative-image "mother" made from them to stamp discs. A major reversal
Berliner Gramophone though this has since been disproven. The Kämmer & Reinhardt venture did not last very long, though just how long is unclear. In the early 1890s, Berliner attempted to found his first American company, the American Gramophone Company, in New York City, but it fell apart before issuing a single machine or disc. Back in Washington, D.C., Berliner tried again under the name of the United States Gramophone Company and began to manufacture machines and 7-inch hard rubber discs in 1894. Some celluloid discs were also made. In 1895, hard rubber was replaced by a shellac compound, which in various