SCIENCE. 



5 



Some distance further on, the passage forks (z). Keep- 

 ing to the right, the dangerous 3 de Saddle Pit (k) is en- 

 countered, which measures 65 feet in depth and 20 feet 

 across. It is surmoun ed by Minerva's Dome, 35 feet 

 high. The pit yawns across the tight half of the floor 

 ot the tunnel, 1-aving a narrow path on the left. 

 A short distance beyond (/), the tunnel again 

 forks. Keeping to the right as before, Gonn's Dome 

 (in ) is reached, and may be viewed with the aid of mag- 

 nesium lights, from a small opening on the side, ten feet 

 above the pathway. The abysm extends 117 feet down- 

 ward, 100 feet upward and 60 feet across. Leaving this 

 and passing the fork (/), the tunnel is completely inter- 

 rupted by the so-called Bottomless Pit ( n ) across which 

 a bridge has been laid, resting upon a ledge. Despite 

 its ominous name it does not defy measurement, having 

 been found to be 95 teet deep on one side of the ledge 

 and 105 feet on the other. Almost immediately overhead 

 is Shelby's Dome, 60 feet high. Between the Bottomless 

 Pit and Side Saddle Pit are a pair of very large pits, dis 

 covered not a year ago by one of the guides, William 

 Garvin, and examined for the first time last August by Mr. 

 Hovey, who gave to them the names Scylla (p) and Cha- 

 ry bdis (o ) on account of the narrow, rugged passage 

 which separates them and the great difficulty and danger 

 of access. By timing the fall of pebbles into the water 

 at the bottom, the depth of each was ascertained to be 

 about 200 feet. Charybdis was seen to be directly con- 

 nected with the Bottomless Pit. Indeed the latter may 

 be regarded as only a part of Charybdis, its depth, 105 

 feet, being only that of a jutting ledge, or the floor upon 

 which water ceased to fall after being slightly deviated 

 into Charybdis, where the sound of its trickling is still 

 audible. Shelby's Dome is simply the upward continua- 

 tion of this combined pit. So narrow, moreover, are the 

 ridges separating Scylla from Charybdis on the one side 

 and from the Covered Pit, (g), on the other, and so small 

 is the distance to the Side Saddle Pit (k), that it seems 

 in the highest degree probable that this group of pits com- 

 pose merely the upper branches of a single large pit into 

 which they are all united, or at least directly connected 

 before the bottom is reached, and the small relative depth 

 of the Side Saddle Pit is explicable in the same manner 

 as that of the Bottomles Pit. Such an extraordinary 

 group of pits, forming an apparent nucleus of cave drain- 

 age, might be expected to have its counterpart in an un- 

 usually large depression, or group of sink-holes, at the 

 surface. Impressed with this idea Mr. Hovey found in 

 the woods, scarcely half a mile from the Hotel, in the 

 known direction of these pits, a depression ( p Fig. 2.), 

 many acres in extent, and so deep that from its edge he 

 could overlook the tops of the pine trees that rose from 

 the middle. 



Leaving this region of pits and domes, the route leads 

 still downward, passing again under the main cave through 

 the narrow tortuous channel known as " Fat Man's Mis- 

 ery " ( s ) where the distance from floor to roof is in many 

 places not more than three feet. Through the floor a 

 winding passage has been worn away, varying in width 

 and depth from one to three feet. This terminates in a 

 chamber which has received the appropriate name of 

 " Great Relief," where the succession of pebbles, gravel, 

 sand and fine clay again records the work of erosion and 

 deposit. This bed is not more than 50 or 60 feet above 

 the drainage level, and from here down to the River Styx, 

 the ground becomes more or less damp. A succession of 

 bodies of water are then encountered, including the tubu- 

 lar Echo River, which is navigated in boats. It is apart 

 of the tunnel which has subsided below the water level, 

 and is in connection with Green River, being filled to 

 within a few feet of the roof in summer, and completely 

 closed in winter when the Green River rises. The col- 

 umn of air between the water and the impervious roof, 

 closed everywhere except at the two ends, which are three- 

 fourths of a mile apart, serves as a resonator for any note 



within the ra"ge of th-; human voice, and multiple echo's 

 gl ding imperceptibly into each other, continue to be re- 

 tur ied for many seconds af.er the voice has been hushed. 



Beyond Echo River, the cave may be followed, with 

 continual ascent, through Silliman's Avenue, the Pass of 

 El Ghor and Cleveland's Cabinet, for about five and a 

 half miles. A pile of jagged rocks, iod feet high, is then 

 surmounted and the wearied climber is confronted with a 

 large cavern, 100 feet wide and 70 feet deep, where three 

 short branches have united in one tunnel. Following the 

 left branch for a few yards, a hall is found, in the floor of 

 which is a pit 175 feet deep. The corresponding dome 

 overhead is scarcely noticeable as such, for the surface of 

 the ground is not more than 30 or 40 feet distant. The 

 end of the Long Route has been reached. 



In returning, the passage through Fat Man's Misery is 

 avoided, and nearly two miles of walking are saved by- 

 climbing through a very steep, narrow, winding " Cork- 

 screw " pass (t, Fig. 2), starting from the neighborhood 

 of Great Relief and terminating at the side of the Great 

 Rotunda. The vertical ascent is about 140 feet. To even 

 stout-hearted mountaineers, if stout-bodied also, this Cork- 

 screw is an intensified Fat Man's Misery, and upon them 

 it rarely fails to leave strong and deep impressions, which 

 may be of more kinds than one. 



In regard to the animal life of the Mammoth Cave, con- 

 flicting opinions have been expressed by those who have 

 made a special study of this subject. The bats, lizards 

 and rats that have been found cannot be strictly called 

 cave-dwellers, as they are always at points not so far re- 

 moved from the outer light as to make this inaccessible, 

 The cave crickets and blind crawfish have particularly 

 long antennae and acute powers of hearing. Most of the 

 crawfish are pale in color, some of them almost white ; 

 and this feature has been attributed to the continued ab- 

 sence of light. Crawfish, however, with well developed 

 eyes and of dark color have been often found. These are 

 without doubt either wanderers from Green River or the 

 immediate descendants of such ; and many generations 

 of cave-dwelling are required to bring about such changes 

 as have caused the application of a specific name, Cam- 

 barus pellucidus, to the white variety with only rudimen- 

 tary eyes. 



In regard to the blind fish it is a significant fact that 

 the rudimentary eyes of the young are apparently less 

 atrophied than those of the mature fish. Although *o 

 these cave dwellers also a specific name, Amblyopsis 

 spelaeus, has been given, they are by no means the only 

 fish found amid this stygian darkness. The existence of 

 fish with perfect eyes, apparently prospering where eyes 

 are useless, shows how much less dependent these crea- 

 tures are than more highly organized vertebrates upon 

 approximate uniformity in external conditions. To those 

 who have already accepted evolution, there is far less diffi- 

 culty in believing that the colorless blind fish are the 

 modified descendants of dark-colored ancestors with per- 

 fect eyes, which have wandered from Green River into 

 Echo River, than in concluding that they have always con- 

 stituted a separate species, as held by Prof. L. Agassiz, 

 and subsequently contended by Prof. F. W. Putnam.* 

 Nevertheless, Prof. Putnam has shown that the differ- 

 ences between the blind fish (A. spelaeus) and their 

 nearest living congeners are much more than in respect 

 to mere color of skin and power of vision. Whether the 

 internal anatomical differences on which he reasonably 

 lays much stress can be proven to be a natural result of 

 the external conditions imposed by cave life, is a question 

 which, if settled at all, must be settled by zoologists alone. 

 Prof. A. S. Packard, Jr., and Prof. E. D. Cope are as pro- 

 nounced in their opinion that the blind fish have been 

 evolved from fresh-water ancestors possessing good 

 vision, as is Prof. Putnam in the opinion that their ances- 

 try were denizens of salt or brackish water, with which 



* The Mammoth Cave and its Inhabitants. By A. S. Packard, Jr., 

 and F. W, Putnam, Salem, Mass., 1879, 



