In 1897 two cave-hunters, Horace Carter Hovey and Richard Ellsworth Call, at first separately then jointly, prepared a manual of the Mammoth Cave. Both of them had made frequent and prolonged visits to the Cave, and were able to say that they had personally seen every part of it then known. They had previously written articles for popular and scientific periodicals, and their membership in scientific societies in this and other lands aided their research. Originally their work was of composite authorship, in the sense that any chapter written by one would be revised by the other. Their aim was to give the latest and most exact word as to cavern history and scenery, heights, depths, dis tances, and magnitudes. Facts not for the first time found here in print were compiled from authentic sources with acknowledgments.