《Scientific American Supplement, No. 664, September 22, 1888》 - 免费有声读物

The Scientific American may be the oldest continuously published periodical in the United States, having launched its first publication in 1845. It has been a mainstay of popular science with in depth articles across a broad spectrum of scientific fields. In this supplement are short articles ranging through such topics as Iron Sailing Ships, Coal Tar as Fuel for Steam Boilers, Pepsin, A Chinese Imperial Cemetery, and Subterraneous Flora and Fauna. - Summary by Larry Wilson