This photo shows a close-up view of the recorded sound groove surface. (Note: The "1565" marking is not historic. It is the NPS museum catalog number.) "Hickory, dickory, dock" ; Edison Talking Doll cylinde More
The groove surface viewed under a microscope. The groove's nearly uniform width shows Edison's early "square-cut" (or "chisel-cut") recording technique. "Twinkle, twinkle little star" ; Edison Talking Doll cyl More
Close-up view of the recorded sound groove surface. "Twinkle, twinkle little star" ; Edison Talking Doll cylinder, metal ; National Park Service collection (EDIS 1279).
"Twinkle, twinkle little star" ; Edison Talking Doll cylinder, brown wax ; National Park Service collection (EDIS 1263).
This photo shows the recorded sound groove surface as viewed under a microscope. "Twinkle, twinkle little star" ; Edison Talking Doll cylinder, brown wax ; National Park Service collection (EDIS 1263).
This photo shows the recorded sound groove surface as viewed under a microscope. "Hickory, dickory, dock" ; Edison Talking Doll cylinder, metal ; National Park Service collection (EDIS 1565).