Jules Verne,
Journey into the Interior of the Earth…
(1877)
“ I thought that my weakened voice could never penetrate to my companions. "It is they," I repeated. "What other men can be thirty leagues under ground?" I again began to listen. Passing my ear over the wall from one place to another, I found the point where the voices seemed to be best heard. The word forlorad again returned; then the rolling of thunder which had roused me from my lethargy. "No," I said, "no; it is not through such a mass that a voice can be heard. I am surrounded by granite walls, and the loudest explosion could never be heard here! This noise comes along the gallery. ”
