Ericsson, John, 1803-1889 · New York : Printed for the author at "The Nation" Press · leaf 594
)paratus. lma-in« … an immense truncated cone, a mammoth lamp-shade, withits concavity directed skyward. This apparatus is of copper,coated on the inside \\\W\ veiy thin silver-leaf. On thesmall ba.se of the truncated cone rests a copper cylinder,blackened on the outside, its vertical axis being identicalwith that of…
![An illustration from [Graphophone patents] (1878)](https://img.insideoutlibrary.com/img/200/ia-graphophonepaten07unit-337-227.webp)
