Title pretty much says it all. They are old recordings (1930s), but man, the tone is amazing. I can only wonder what he’d sound like using modern equipment. I believe they used to make these straight to disc. Disc, meaning waxed disc. You can learn a little about the technology here and here (take Wikipedia with a grain of salt though).
The recordings are housed here:
http://www60.tok2.com/home/sonore/