40 THE FOSSIL SLOTH AT BIG BONE CAVE, TENN. [Jan. 15, 



one mile above the mouth of a confluent called Dry Branch, in Van 

 Buren county, Tenn., probably looo feet above the sea, Big Bone 

 cave opens from the carboniferous limestone upon the head of the 

 "Beech cove," one of the secluded ravines called "coves" that 

 furrow the western slope of the Cumberland table land. Though 

 600 feet, more or less, and a broken reach of country intervened 

 between the cavern and the high cool region above, its general near- 

 ness to the plateau^ and its elevation promised well for the explorer. 

 Subterranean deposits washed away, or disturbed by water, during 

 the supposed invasion of the lower country by post-glacial floods, 

 might well have escaped destruction in a cave lying as high as this, 

 while the chance of unearthing abundant or ancient mammalian 

 remains was increased, if we were to suppose that animals in great 

 numbers had gathered in the vicinity, or that man, if he ex- 

 isted, had sought refuge upon the plateau during a general inunda- 

 tion. 



But the configuration of the cave, at its entrance, disappointed 

 us. By all past experience, the gloomy hole (see Fig. i) over- 

 shadowed with large " tulip trees " was too wet and steep for savage 

 shelter. Water dripped from the low arch forty-two feet wide and 

 only six feet high. The down-washing of rain from the hill above 

 had choked the vault with loose stones, and disturbed any deposit 

 of earth that may ever have existed within sight of the outer world. 

 Just where we had expected to discover evidence of value, at the 

 point where caves are usually richest in significant remains, there 

 was no work for shovel and pickaxe. To our surprise, the point of 

 interest in Big Bone cave lay far beyond the reach of daylight. It 



1 The Cumberland table-land, a flat-topped continuation of the AUeghenies 

 with sandstone top set on limestone base, extending from northeast to south- 

 west across the entire State of Tennessee, comprises, according to Prof. Safford, 

 5100 square miles, or one-eighth of the State. Rising 1000 feet above the valley 

 of Tennessee and 2000 feet above the sea, its eastern edge forms a generally straight 

 line, while its western escarpment is notched and scalloped by deep "coves" 

 and valleys, where erosion has laid bare the underlying stratum of " mountain " 

 (carboniferous) limestone upon which the plateau is founded. At almost all 

 points on both sides, the surface suddenly breaks off in sandstone bluffs or 

 cliffs from twenty to two hundred feet in height, giving generally a sharp and promi- 

 nent margin or brow to the plateau. The carboniferous sandstone surface of the high 

 region, overspread with a sandy, coarse and sterile soil, is often flat for miles. Then 

 again it is rolling and diversified with hills and shallow valleys. In the northeastern 

 part there are high ridges containing many beds of coal, which may be regarded as 

 mountains on a table-land. See Elementary Geology of Tennessee, by J. M. Safford, 

 Nashville, p. 32. 



