February 15, 1889.] 



SCIENCE. 



short distance south of the mail-route, which, leaving Lamar River, 

 follows up Soda Butte Creek to the mining-camp of Cooke City. 

 In this region the lavas which fill the ancient basin of the park rest 

 upon the flanks of mountains formed of fragmentary volcanic 

 ejecta, the tertiary andesitic breccias, which rest in turn upon 

 nearly horizontal paleozoic strata ; while the hydrothermal forces, 

 vifhich are represented by the geysers and hot springs of the cen- 

 tral portion of the park, where the lava-sheet is thicker, show but 

 feeble manifestations of their energy in the almost extinct hot- 

 spring areas of Soda Butte, Lamar River, Cache Creek, and Miller 

 Creek. Although hot water no longer flows from the vents of 

 these areas, the deposits of travertine, sinter, and decomposed rock, 

 attest the former presence of thermal springs. Gaseous emana- 

 tions are now given off, however, in considerable volume, producing 

 extensive alteration in the adjacent rocks, and giving rise to sul- 

 phurous deposits. 



It is at one of these places that the fatal ravine is found. Situ- 

 ated on Cache Creek, but two miles above its confluence with La- 

 mar River, it is easily reached by a horseback ride of some five 

 miles from the mail station of Soda Butte. The region is, however, 

 rarely visited; for hunting is forbidden in the park, while the place 

 has not been known to present any attraction for the few visitors 

 who pass near it on their way to the well-known Fossil Forests and 

 the weird scenery of the Hoodoo basin. 



An old elk-trail, which runs along the north bank of Cache 

 Creek, affords easy travelling, and leads to a little opening in the 

 pine-forest bordering on the stream. In the centre of the meadow 

 is a shallow depression, once the bed of a hot-spring pool, now dry, 

 and covered with an efflorescence of salt, making it attractive to 

 the elk and other game of the region as a " lick." The banks of 

 the creek opposite this meadow and below it are covered with the 

 ancient hot-spring deposits, which are very dense and hard, and at 

 the borders of the stream have been polished by the action of the 

 water until the surface shines like glass. A hot-spring cone half 

 washed away by the creek, and a mound of altered travertine on 

 the opposite bank, show the character of the ancient hot-spring 

 water, the rippled surface of the deposit being exactly like that of 

 the beautiful terraces and slopes of the Mammoth Hot Springs. 

 At present, however, the only thermal action is the emission of a 

 little tepid sulphurous water at the edge of the stream. On the 

 other hand, the gaseous emanations are very striking and abun- 

 dant. 



In the middle of the creek, which here forms a deep pool about 

 thirty feet across, bordered by the polished calcite already men- 

 tioned, the water boils up furiously at several places. This water 

 is, however, quite cold ; and the " boiling " is caused by the very 

 copious emission of gas, mainly, no doubt, carbonic acid, though 

 containing some sulphuretted hydrogen, since its smell is quite 

 noticeable, and the water is slightly turbid with particles of sul- 

 phur, which also coat the sides and bottom of the pool. Rising 

 through the water of the creek, the great amount of gas given off at 

 this place is easily appreciated, but equally copious emanations may 

 occur from the deposits and old vents near .by, which, being invisi- 

 ble, remain unnoticed. 



Above these deposits of altered and crystalline travertine, the 

 creek cuts into a bank of sulphur and gravel cemented by this ma- 

 terial, and a few yards beyond is the debouchure of a small lateral 

 guUey coming down from the mountain-side. In its bottom is a 

 small stream of clear and cold water, sour with sulphuric acid, and 

 flowing down a narrow and steep channel cut in beds of dark gray 

 volcanic tuff. Ascending this gulch, the sides, closing together, 

 become very steep slopes of v\'hite decomposed rock, the silicious 

 residue formed by the decomposition of the rocks by acid vapors 

 or waters. The only springs now flowing are small oozes of water 

 issuing from the base of these slopes, or from the channel-bed, and 

 forming a thick, creamy, white dept)sit about the vents, and cover- 

 ing the stream-bed. This deposit consists largely of sulphate of 

 alumina. The slopes show local areas where sulphur has been de- 

 posited by the oxidation of sulphurous vapors, but no extinct hot- 

 spring vents were found. About one hundred and fifty feet above 

 the main stream, these oozing springs of acid water cease ; but the 

 character of the gulch remains the same. The odor of sulphur 

 now becomes stronger, though producing no other effect than a 



slight irritation of the lungs. The gulch ends, or rather begins, in 

 a " scoop " or basin about two hundred and fifty feet above Cache 

 Creek ; and just below this we found the fresh body of a large bear, 

 a silver-tip grisly, with the remains of a companion in an advanced 

 state of decomposition above him. Near by were the skeletons of 

 four more bears, with the bones of an elk a yard or two above ; 

 while in the bottom of the pocket were the fresh remains of several 

 squirrels, rock-hares, and other small animals, besides numerous 

 dead butterflies and insects. The body of the grisly was carefully 

 examined for bullet-holes or other marks of injury, but showed no 

 traces of violence, the only indication being a few drops of blood 

 under the nose. It was evident that he had met his death but a 

 short time before, as the carcass was still perfectly fresh, though 

 offensive enough at the time of a later visit. The remains of a cin- 

 namon bear just above and alongside of this were in an advanced 

 state of decomposition, while the other skeletons were almost de- 

 nuded of flesh, though the claws and much of the hair remained. 

 It was apparent that these animals, as well as the squirrels and in- 

 sects, had not met their death by violence, but had been asphyxi- 

 ated by the irrespirable gas given off in the gulch. The hollows 

 were tested for carbonic-acid gas with lighted tapers without prov- 

 ing its presence ; but the strong smell of sulphur, and a choking 

 sensation of the lungs, indicated the presence of noxious gases, 

 while the strong wind prevailing at the time, together with the open 

 nature of the ravine, must have caused a rapid diffusion of the 

 vapors. 



This place differs, therefore, very materially from the famous 

 Death Valley of Java jnd similar places in being simply a V-shaped 

 trench, not over seventy-five feet deep, cut in the mountain-slope, 

 and not a hollow or cave. That the gas at times accumulates in the 

 pocket at the head of the gulch, is, however, proven by the dead 

 squirrels, etc., found on its bottom. It is not probable, however, 

 that the gas ever accumulates here to a considerable depth, owing 

 to the open nature of the place and the fact that the gulch drain- 

 ing it would carry off the gas, which would, from its density, tend 

 to flow down the ravine. This offers an explanation of the death 

 of the bears whose remains occur, not in this basin, but where it 

 narrows to form the ravine; for it is here that the layer of gas 

 would be deepest, and has proven sufficient to suffocate the first 

 bear, who was probably attracted by the remains of the elk, or per- 

 haps of the smaller victims of the invisible gas ; and he, in turn, 

 has doubtless served as bait for others who have in turn succumbed. 

 Though the gulch has doubtless served as a death-trap for a very 

 long period of time, these skeletons and bodies must be the re- 

 mains of only the most recent victims ; for the ravine is so narrow 

 and the fall so great, that the channel must be cleared out every 

 few years, if not annually. The change wrought by the water 

 during a single rain-storm, which occurred in the interval be- 

 tween my first and second visits, was so considerable that it seems 

 probable that the floods of early spring, when the snows are melt- 

 ing under the hot sun of this region, must be powerful enough to 

 wash every thing down to the cone of debris at the mouth of the 

 gulch. 



Gaseous emanations are very frequent in volcanic countries, and 

 may be either temporary or permanent. The former are, as is well 

 known, particularly abundant after volcanic eruptions. The gases 

 emitted from fissures in the flanks of Vesuvius are said to have 

 killed thousands of hares and pheasants, and whole herds of cattle 

 have been suffocated by volcanic gas given off near Quito. The 

 permanent emissions of gas, such as the mofettes of Italy, the 

 Laacher See, and the Auvergne, remain unchanged, however, for 

 centuries. Where carbonic-acid gas is evolved from a fairly uni- 

 form surface, it is quickly diffused into the atmosphere upon the 

 slightest movement of the air ; but the case is quite different when 

 the gas is emitted in caves or hollows in the ground. In such 

 places it accumulates, because of its density and slow diffusion, un- 

 til the hollows are filled to the brim, any excess being quickly dif- 

 fused as from a level surface. Small hollows of this kind occur in 

 the travertine deposits of the Mammoth Hot Springs of the park, 

 and near the Hot Lakes of the Lower Geyser basin. In these 

 places, small birds, mice, etc., attracted by the warmth of the va- 

 pors, or the dead insects, are often suffocated by the gases. Such hol- 

 lows resemble the mofettes of the Laacher See in Germany, where 



