in august 1927, electrical recording began, making edison the last major record company to adopt it, over two years after victor records, columbia records, and brunswick records had converted from acoustical recording. sales continued to drop, however, and although edison diamond discs were available from dealers until the company left the record business in late october 1929, the last vertically cut direct masters were recorded in the early summer of that year. priority had been redirected to introducing a new line of edison lateral or so-called needle type thin shellac records, compatible with ordinary record players, but although their audio quality was excellent this concession to commercial reality came too late to prevent the demise of the edison phonograph and records division just one day before the 1929 stock market crash.