Howell appealed the case to the U. S. District Court sitting at Cheyenne, Wyoming, and was released upon the technical ground that, as the prohibition against returning to the Park was merely an order from the Superintendent, and not explicitly authorizedby the regulations of the Secretary of the Interior, the offense did not come within the purview of the law. This defect in the regulations has since been remedied and the conviction of Howell, therefore, notwithstanding his final release, has all the force of precedent.
PART II.—Descriptive.
CHAPTER I.
BOUNDARIES AND TOPOGRAPHY.
At the time when the bill creating the Yellowstone Park was before Congress there had been no detailed survey of that region, and the boundaries, as specified in the bill, were to some extent random guesses. The exploring parties of 1870 and 1871 had seen all the more important points of interest. To include these in the proposed reservation, the framers of the bill passed two lines due east and west, one through the junction of the Yellowstone and Gardiner Rivers, and one through a point ten miles south of the most southerly point of the Yellowstone Lake; and two lines due north and south, one through a point ten miles east of the easternmost point of Yellowstone Lake, and one through a point fifteen miles west of the most westerly point of Shoshone (then called Madison) Lake. The nearly rectangular area thus resulting was found to lie mainly in the north-west corner of Wyoming, with narrow strips, two or three miles wide, overlapping into the Territories of Montana and Idaho. The mean dimensions of the Reservation were 61.8 miles by 53.6 miles, giving an area of 3312.5 square miles.
By presidential proclamation, dated September 10, 1891, a large area to the east and south of the Parkwas set apart as a Forest Reserve, under the provisions of an Act of March 3, 1891, and was placed in charge of the Superintendent of the Park. By this action the area reserved from settlement around the sources of the Yellowstone was increased to about 5,000 square miles. It should be remembered, however, that this additional reserve is not a direct creation by Act of Congress, and it therefore does not stand upon the same substantial footing as the original Reservation.
The chief topographical features of the Park are as follows:
DRAINAGE AREAS.
Three great rivers receive the waters of the Yellowstone Park—the Yellowstone, the Missouri, and the Snake. The first two rivers are on the Atlantic slope; the third is on the Pacific slope. The areas drained by them are approximately:
The Yellowstone River has its source in the snow drifts of Yount Peak, twenty-five miles south-east of the Park. It enters the Reservation six miles west of the south-east corner; crosses it in a direction somewhat west of north, and leaves it at a point about nineteen miles east of the north-west corner. Near the center of the Park it flows through the celebrated lake of the same name, and further north passes through two remarkable cañons before it leaves the Reservation. Its principal tributaries within the Park are the Lamar River (commonly called the East Fork), from the east, and Gardiner River from the west.The Lamar River rises nearly due east of the outlet of Yellowstone Lake and flows north-westerly, joining the main stream near Junction Butte. Its principal tributary is Soda Butte Creek, which rises just outside the north-east corner of the Park and joins the Lamar River near the extinct hot spring cone from which it derives its name.
Gardiner River is the second largest tributary of the Yellowstone, and drains the extensive area between the Washburn and Gallatin Mountains.
The low-water discharge of the Yellowstone River, as measured by the writer, in 1891, a little below the lake outlet, is 1,598 cubic feet per second; as measured by the United States Geological Survey, in 1886, 1,525 cubic feet. The discharge at the north boundary of the Park can not be less than 2,000 cubic feet.
The Missouri River drainage flows into the Gallatin and Madison forks of that stream. The Gallatin drains only a small area in the extreme north-west corner of the Park. The Madison is formed by the junction of the Gibbon and Firehole Rivers, about twelve miles east of the west boundary of the Park. The Gibbon takes its rise a few miles west of the Falls of the Yellowstone, and flows in a south-west direction. The Firehole rises in Madison Lake, and flows north to its junction with the Gibbon. Its principal tributaries are the Little Firehole River and Iron Creek on the west, and Nez Percé Creek on the east.
The Snake River drains the south-west portion of the Park. It rises about fifteen miles south of Yellowstone Lake, just outside the Park. It then takesa northerly circuit into the Park, receiving the waters of Hart and Lewis Rivers, and leaves the Reservation just north of Jackson Lake. Its principal tributary is the Lewis River, which drains Shoshone and Lewis Lakes. Several large streams, Bechler and Falls Rivers among them, cross the south-west boundary of the Park and join the main Snake further south.
The line of separation between this water-shed and those of the Yellowstone and the Missouri, is the Continental Divide, the irregular course of which can be readily understood by consulting the map.
In the entire Park there are about thirty-six named lakes with a total area of nearly 165 square miles. Of these lakes, twenty-one, with an area of 143 square miles, are on the Yellowstone slope; eight, with an area of perhaps two square miles, are on the Missouri slope; and seven, with an area of about twenty square miles, are on the Snake River slope. The four principal lakes—Yellowstone, Shoshone, Lewis, and Hart—are clustered near the Continental Divide at its lowest point, the first being on the Atlantic slope, and the others on the Pacific.
There are upon the various streams of the Park no fewer than twenty-five interesting water-falls, where the streams descend from the Park plateau to the lower surrounding country.
MOUNTAIN SYSTEM
As the Yellowstone River is the most important stream in the Park, so the Absaroka Range, in which it has its source, is the most important mountain system. It extends north and south along the entire eastern border. To the south it is prolonged underthe name of the Sierra Shoshone Mountains as far as the Wind River Valley, while north of Soda Butte Creek it extends to the Great Bend of the Yellowstone under the name Snowy Range. The various larger summits are remarkably uniform in elevation. From Index Peak on the north to Yount Peak on the south, there are more than thirty named mountains with an average altitude of 10,400 feet. The variation from this mean is slight. The range, throughout its length, is full of noble views, and, as seen from across the Yellowstone Lake, is one of the finest exhibitions of mountain scenery on the continent.
The next most important range is the Gallatin, situated in the north-west corner of the Park, at the head of the Gallatin River. It has about seventeen named peaks, with an average altitude of 9,800 feet. The highest peak, Electric, is the loftiest mountain in the Park.
The Washburn Range, a detached mountain system, originally known as the “Elephant’s Back,” is situated between the Grand Cañon of the Yellowstone and the Gardiner River. It has seven christened summits, with an average altitude of 9,800 feet. The most conspicuous peak of the range, as well as the most noted mountain of the Park, is Mt. Washburn.
The Red Mountain Range is a small, detached group of mountains between Hart and Lewis Lakes. Its principal summit, Mt. Sheridan, affords probably the finest view to be had in that entire region.
The Teton Range lies mainly outside the Park, its northern spurs barely touching the southern boundary. It extends north and south along the west shore ofJackson Lake, and is a very noted range of mountains. Its highest summit, the Grand Teton, has no competitor for altitude nearer than Fremont Peak, seventy-five miles distant.
The Big Game Ridge lies along the south boundary of the Park, and is the source of the Snake River. It has six named peaks, with an average altitude of 9,800 feet.
Besides these various groups of mountains, there are a few detached peaks worthy of note, which can not be conveniently classified with any of the principal ranges.
PLATEAUS.
A considerable portion of the Park area is composed of what may be termed plateaus, elevated tracts of land, not so high as the mountain ranges, but much higher than the valleys. Ordinarily, these are to be found along the divides between the larger streams. The more important are the Pitchstone Plateau, between the Snake River and the head waters of the Bechler and Fall Rivers, with a mean altitude of 8,500 feet; Highland Plateau, between the Yellowstone and the Madison Rivers, altitude 8,300 feet; Mirror Plateau, between the Yellowstone and the Lamar Rivers, altitude 9,000 feet;Mt. Everts Plateau, between the Yellowstone and the Gardiner, altitude 7,000 feet; and the Madison Plateau, west of the Lower Geyser Basin, altitude 8,300 feet.
VALLEYS.
These form an exceedingly important part of the Park topography. The largest is Junction Valley, including its branches along the Yellowstone and theLamar Rivers. It is an extensive, grassy tract, stretching well back upon the mountain sides, and forming a fine pasturage for game. For scientific research, its fossil forests and other features make it an extremely interesting section.
Hayden Valley is the next in size and importance, and occupies an important tract along the Yellowstone River, between the Lake and Falls, mostly on the west side, in the vicinity of Alum Creek.
The Madison Valley, and its extensions up the Firehole and Gibbon Rivers, are chiefly noteworthy as being the locality of the three great geyser regions of the Park.
The Swan Lake Flats, Willow Park, the Shoshone and Falls River Basins, are other important examples of typical mountain valleys.
ALTITUDES.
The lowest point in the Park is at the junction of the Yellowstone and the Gardiner Rivers, 5,360 feet above sea level; the highest is the summit of Electric Peak, six miles distant, 11,155 feet. To give a general idea of the altitudes of different points in the Park, particularly of those which the tourist visits, the following list is presented:[AT]
[AT]From profile of road system. For additional elevations, see list of names inAppendix A.
[AT]From profile of road system. For additional elevations, see list of names inAppendix A.
SCENERY.
The mountain scenery of the Park is not so imposing as that of Colorado and some other parts of the Rocky Mountain region; but it is more varied and beautiful. The eye is not wearied with the constant sight of vast and bare mountain cliffs, but finds relief in attractive lakes, streams, glades, parks, forests, and every combination of effects that helps to produce a beautiful landscape.
CHAPTER II.
Geology of the Park.
Nature seems, from the first, to have designed this region for a mountain park. In geological chronology it was near the close of the Cretaceous Period, that the lifting of the great mountain systems of the West into their present positions was practically finished. In the formation of these mountains, the general outline of the Yellowstone Park was already marked out, probably in much more striking features than at present. A vast rim of mountains, visible now in the Absaroka, Snowy, Gallatin, Teton, and Snake River Ranges, hemmed in the extensive area which has since become so famous. Subsequent events have greatly modified its original form, but the grand outlines at first determined are still distinctly visible.
In the Tertiary Period, which was next in order of time after the Cretaceous, changes of the greatest importance occurred, consisting principally in the outpouring of enormous masses of volcanic material. The origin of these lava flows has been traced to a few craters, one of which was near Mt. Washburn, another in the Red Mountain Range, and a third near the sources of the Lamar River. Mt. Washburn has long been recognized as part of the rim of an ancient volcano. Both it and Mt. Sheridan, the two mountains which bore the principal part in working out the present features of that country, still remain the mostprominent peaks from which the modern visitor can contemplate the work they have performed.
The outpourings at first consisted of andesitic lavas. They largely changed the appearance of the mountain ranges and to some extent filled up the interior basin. The flows were not continuous but were separated by long intervals of quiet, during which vegetation and the agencies of erosion were actively at work.
After the cessation of the andesitic eruptions, a quiescent period of great length ensued. Then came the period of rhyolitic flows, the centers of volcanic activity being as before Mts. Washburn and Sheridan. These flows built up the present Park plateau, and constitute the great bulk of the rocks which the tourist now sees.
Following the period of rhyolitic eruptions, orographic agencies were active in producing extensive faults or displacements, which in certain localities radically changed the relative positions of the rocks.
The last exhibitions of volcanic energy were in the form of basaltic eruptions. These took place in part through ordinary volcanic craters, and in part through cracks or seams in the rocks, where they may still be seen forming extensive dykes. The basalt is of relatively limited extent, but its striking and picturesque forms wherever it appears make it more interesting to the tourist than any of the other rocks.
The great variety of superficial appearances which these volcanic rocks have assumed makes the Park one of the best laboratories in the world for their study.
The continuance of these various outpourings doubtless extended into Quaternary time. Then came theGlacial Epoch, the epoch of wide-spread ice-carving, which still further modified the surface of the country. The paths of the ancient glaciers have in several instances been made out and their transported material may readily be distinguished. One glacier flowed from the Gallatin Range eastward across Terrace Mountain, where it joined another moving westwardly from the Absaroka Range. The united streams continued down the Gardiner and Yellowstone Valleys, in which vast masses of drift still mark their ancient route.
Glacial action and the common agents of denudation have given the Park country its present general aspect. These later modifications have indeed been extensive, and the great variety of form now seen in the valleys, cañons and hills is the result of their combined action. The Yellowstone Cañon is a marked example of erosion on a large scale. A direct result of its formation was the partial draining of Yellowstone Lake, which had previously existed at a much higher level than now, and spread over the entire area of the present Hayden Valley.
Since the cessation of the basaltic lava flows there seem to have been no further lava outpourings in this region. The old volcanoes have been long extinct and their craters have been modified almost beyond recognition. But evidences of the power which once worked beneath them are still abundant, although no longer on so imposing a scale. It is the hot springs and geysers still in existence which partly render this region so widely celebrated. That this thermal action originates mainly in the same source of energy which once poured out the vast fields of lava, there is noreason to doubt. Many plausible explanations are advanced to account for the existence of subterranean heat, but whatever may be its real origin it is doubtless the same for both classes of phenomena.
The action which is now observable has continued in an ever-decreasing degree since the close of the lava period. Over vast tracts of the Park plateau, the rocks are entirely decomposed to unknown depths by the ascending superheated vapors. Some idea of the extent of this action may be obtained at the Grand Cañon, which has cut its way a thousand feet downward into the decomposed volcanic rock without yet reaching its bottom. The infinite variety of chemic products resulting from this decomposition has given the Cañon its wonderful coloration.
The same condition largely prevails over the Park plateau. Where now are dense forests and no superficial evidence of unusual conditions, there will frequently be found, by digging beneath the surface, the familiar proof that thermal activity once prevailed there. In constructing the tourist route from the Upper Geyser Basin to the Yellowstone Lake, where for nearly the whole distance there is a complete absence of hot springs, the evidences of former volcanic activity were found to be abundant.
Facts like these clearly demonstrate that, from a geologic standpoint, thermal activity in the Park is gradually becoming extinct; and many persons, taking alarm at this evidence, imagine that the unique phenomena of the Yellowstone are of an evanescent character, and that the time is not far remote when they will be known only as matters of history. There is, however, no occasion for such misgiving. Thepresent condition is the result of processes that run back probably for millions of years; certainly for periods of time compared with which recorded history is insignificant. The same rate of progress would produce no perceptible change in the lifetime of an individual.
Some who have visited the geyser regions more than once assert that, after an interval of several years, they observe a marked diminution in thermal activity. But this is probably because a second visit ordinarily makes a less vivid impression than a first. The weight of reliable evidence is certainly the other way. Mr. David E. Folsom, leader of the Expedition of 1869, made a tour of the Park during the present season of 1895. He says: “I had a very vivid recollection of all I saw twenty-six years ago, and I note no important change.” Professor Arnold Hague, probably the best living authority upon the scientific features of the Park, has compared the hot springs and geysers by means of authentic records covering intervals of several years, and he declares that he finds “no diminution in the intensity of action or in the amount of discharge from the springs and geysers, since they have been subject to careful observation.” While it is certain that springs are constantly becoming inactive, it is no less certain that others replace them, and it may be confidently assumed that the progress toward ultimate extinction will be inappreciable in our time or for many generations to come.
The distribution of thermal springs over the surface of the earth is probably more general than is commonly supposed. Only one extensive area is practically without them, and that is the Continent of Australia.Africa, also, has very few. But in other parts of the globe they are found almost without number, ranging from the Equator to the Arctic Circle, and from sea-level to the lofty table lands of Thibet.
The three localities, however, in which they abound in such numbers and magnitude as to attract marked attention are, in the order of their discovery, Iceland, New Zealand, and the Yellowstone National Park. In extent, variety, and magnitude of accompanying phenomena, and in geologic age, the above order is reversed. Iceland has probably the most famous geyser in the world, principally because it was for a long time the only known geyser, and consequently received a great deal of scientific attention; but judging from published descriptions it is clearly inferior to several now known in the Firehole Geyser Basin.
Three notable features of similarity in these geyser regions are the presence of volcanic rocks of remote or recent origin; proximity to the earth’s surface of active sources of subterranean heat; and the presence of a great number of lakes. In all three cases, lava, heat and water are the characteristic geologic and physical accompaniments of those particular phenomena which will now be described more in detail.
CHAPTER III.
GEYSERS.
The hot springs of the Yellowstone National Park may be roughly divided into two classes, eruptive and non-eruptive. To the first the termgeyseris applied, while the termhot springsis restricted to the second. These two classes pass into each other by insensible gradations and the line of demarcation it is not possible to draw. The following description will pertain only to those examples about which there is no doubt, and which may be taken as types of their class.
A geyser may be defined as a periodically eruptive hot spring. The name, as might be expected, is of Icelandic origin, and comes from the verbgeysa,to gush. The general characteristics of a true geyser, as illustrated by the most perfect example known, Old Faithful in the Yellowstone Park, are the following:
(1.) There is an irregular tube descending from the earth’s surface to some interior source of heat.
(2.) The mouth of this tube may be either a self-built mound or cone (as in the example), or simply an open pool.
(3.) Into this tube meteoric water finds its way and is subjected to the action of heat.
(4.) The result is an eruption and expulsion of the water from the tube with more or less violence.
(5.) The eruption is generally preceded by slight preliminary upheavals leading gradually to the final outburst.
(6.) After cessation of the eruption there is usually a considerable escape of steam.
(7.) A quiescent period, generally of indeterminate duration, follows during which the conditions necessary for an eruption are reproduced.
Geyser phenomena have attracted a great deal of scientific attention, and many theories have been advanced to explain them. Passing over for the present the various less important views, attention will first be given to Bunsen’s theory, because it is, upon the whole, the most satisfactory explanation yet advanced. This theory was a direct deduction from observations upon the Great Geyser of Iceland, and has been experimentally illustrated by artificial examples.
The fundamental principle upon which it is based is the well known fact that the temperature of the boiling point of water varies with the pressure to which the water is subjected. At the sea level, under the pressure of one atmosphere (fifteen pounds to the square inch), the boiling point is about 212 degrees Fahrenheit. Under a pressure of two atmospheres it is 250 degrees; of three, 275 degrees; of four, 293 degrees, and so on. At an altitude like that of the Park plateau, where the atmospheric pressure is much less than at sea level, the normal boiling point is about 198 degrees, but the law of variation due to pressure conditions applies exactly as in lower altitudes.
If water, subjected to great pressure, be heated to a temperature considerably above that of its normal boiling point, and if then the pressure be suddenly relieved, it will almost instantaneously be converted into steam; a fact which always operates to enhance the danger from the explosion of steam boilers. Applyingthis principle to the case of an ordinary geyser, it will readily be seen that in the long irregular tube descending to great depths there are present the necessary conditions for subjecting the water to great pressure. At the surface the pressure is that of the weight of the atmosphere corresponding to the altitude; at a certain depth below (33 feet at the sea level, but less at higher altitudes) it is twice as great; at double this depth three times as great, and so on.
Suppose, now, that there is an interior heat at some point along the geyser tube well below the surface. The boiling point of water in the vicinity of the heat supply will be higher than at the surface in definite relation to its distance down. If the tube be of large diameter and the circulation quite free, the water will never reach this point, for it will rise nearer the top, where the boiling point is lower and will pass off in steam. The spring will thus be simply a boiling or quiescent spring. But if the tube be comparatively small and if the circulation be in any way impeded, the temperature at the source of heat will rise until it reaches a boiling point corresponding to its depth. Steam will result, and will rise through the water, gradually increasing the temperature in the upper portions of the tube. After a time the water throughout the entire tube becomes heated nearly to the boiling point and can no longer condense the steam rising from below; which then rapidly accumulates until its expansive power is great enough to lift the column above and project some of the water from the basin or cone. This lessens the weight of the column and relieves the pressure at every point. In placeswhere the water had been just below the boiling point, it is now above, and more steam is rapidly produced. This throws out more water, still further lightens the column, and causes the generation of more steam, until finally the whole contents of the tube are ejected with terrific violence.
From this explanation it is apparent that any thing which impedes the circulation of water in the geyser tube will expedite the eruption. The well-known effect of “soaping geysers” may thus be accounted for. As oil thrown upon waves gives a viscosity to the surface, which greatly moderates their violence, so does the addition of soap or lye make the water of the geyser tube less free to circulate, and thus hasten the conditions precedent to an eruption.
The apparently contrary process of violently agitating the water of the geyser, as by stirring it with a stick, sometimes produces the same effect; but this results from the sudden forcing upward of masses of superheated water, instead of allowing them to rise and gradually cool.
That Bunsen’s theory really explains the phenomena of geyser action there can be little doubt. It is true that in no single geyser does one find a perfect example of the theory. But it must be remembered that typical conditions probably never exist. The point of application of heat; the mode of application, whether from the heated surface of rocks or from superheated steam issuing into the tube; the diameter and regularity of the tube; the point of inflow of the cold water; are all matters which influence the eruption and determine its character. In the endless variety of conditions in nature one need not wonderat the varying results. He should rather wonder that in a single instance nature has produced a combination of such perfection as is found in Old Faithful, which, for thousands of years has performed its duty with the regularity of clock work.
There are various other theories, each with some particular merit, which may be briefly referred to. Sir George Mackenzie, who visited Iceland in 1810-11, thought the geyser tube at some point beneath the surface curved to one side and then upward, communicating with a chamber in the immediate vicinity of the source of heat. The water in this chamber becomes heated above the boiling point, and, expanding, forces the water from the chamber into the tube until the chamber is finally emptied to the level of the mouth of the tube. Any further expulsion of water lessens the weight of the column of water above. Bunsen’s theory comes into play, and with the accumulated pressure of the steam in the chamber, produces a violent eruption.
Prof. Comstock, who visited the Park in 1873, thought that there were two chambers, the lower being in contact with the source of heat, and the upper acting as a sort of trap in the geyser tube. After a sufficient force of steam has accumulated in the lower chamber, it ejects the contents of the chamber above.
S. Baring-Gould, who visited Iceland in 1863, observed that if a tube be bent into two arms of unequal length, the shorter of which is closed, and if the tube be filled with water and the shorter arm then heated, all the characteristic phenomena of geyser action result,the water being finally ejected, with explosive violence from the longer tube.
Now, it is probable that in nature each of these theories may find illustration, but it must still be acknowledged that in all cases Bunsen’s theory is the partial explanation, and in many the only adequate one.
The most superficial examination of the geysers in the Park will disclose two widely different characteristics as regards their external appearance and mode of eruption. On this basis they may be divided into two classes—the fountain geysers and the cone geysers.
In the fountain geyser there is no cone or mound, but in its place a considerable pool which in intervals of rest bears perfect resemblance to the larger quiescent springs. The eruption generally consists of a succession of prodigious impulses by which vast quantities of water are thrown up one after another. There is ordinarily no continuous jet. To geysers of this class, Mackenzie’s and Comstock’s theories would seem to find closer application than to any others. Noted examples are the Fountain, the Great Fountain, the Grand and the Giantess Geysers.
The cone geysers, on the other hand, have no pool about the crater, and water is not generally visible in the tube. There is always a self-built cone or mound of greater or less prominence, ranging from a broad gently-sloping mound, like that of Old Faithful, to a huge cone like that of the Castle. The eruptions from these geysers usually take the form of a continuous jet, and are more in accordance with the theoryof Bunsen. Prominent examples are the Giant, the Castle, Old Faithful, the Lone Star, and the Union.
Terry Engr. Co.U. S. Geological Survey of the Territories.Cone of the Giant Geyser.
Terry Engr. Co.
U. S. Geological Survey of the Territories.
Cone of the Giant Geyser.
Terry Engr. Co.First sketch ever made.[AU]—Trumbull.Cone of Giant Geyser.[AU]This sketch and a similar one of the Castle Geyser cone and two of the Yellowstone Falls are thevery firstever made of these objects. They were made in 1870 by Walter Trumbull, a member of the Washburn Party, and by Private Charles Moore, one of the escort under Lieutenant Doane. Moore was a man of excellent education and considerable culture, and it was a matter of comment among the members of the Expedition that he should be content with the condition of a private soldier. His quaint sketches of the Falls forcibly remind one of the original picture of Niagara made by Father Hennepin in 1697.
Terry Engr. Co.
First sketch ever made.[AU]—Trumbull.
Cone of Giant Geyser.
[AU]This sketch and a similar one of the Castle Geyser cone and two of the Yellowstone Falls are thevery firstever made of these objects. They were made in 1870 by Walter Trumbull, a member of the Washburn Party, and by Private Charles Moore, one of the escort under Lieutenant Doane. Moore was a man of excellent education and considerable culture, and it was a matter of comment among the members of the Expedition that he should be content with the condition of a private soldier. His quaint sketches of the Falls forcibly remind one of the original picture of Niagara made by Father Hennepin in 1697.
An interesting and singular fact pertaining to this region is that in most cases the springs and geysers have no underground connection with each other. Water in contiguous pools stands at different levels, and powerful geysers play with no apparent effect upon others near by.
It is another interesting question to know whence comes the water for these geysers and hot springs. Into the hidden caverns of “Old Faithful” flow nearly a million of gallons per hour. This is a large stream, but it is a mere trifle compared with the entire outflow of hot water throughout the Park. The subterranean passages by which the necessary supply is furnished to all these thousands of springs, certainly constitute the most intricate and extensive system of water-works of which there is any knowledge.
Not least wonderful of the features of the great geysers are the marvelous formations which surround them, more exquisitely beautiful than any production of art. They are really much handsomer than those to be found around the ordinary quiescent springs. The falling or the dashing of the hot water seems to be in some way essential to the finest results. To say that these rocky projections simulate cauliflower, sponge, fleeces of wool, flowers or bead-work, conveys but a feeble hint of their marvelous beauty. It is indeed amost interesting fact that nature here produces in stone, by the almost mechanical process of deposition from cooling water, the identical forms elsewhere produced by the very different processes of animal and vegetable life.
Terry Engr. Co.U. S. Geological Survey of the Territories.Specimens of Geyserite.
Terry Engr. Co.
U. S. Geological Survey of the Territories.
Specimens of Geyserite.
These formations are all silica and are of flinty hardness. Bunsen, and Prof. Le Conte following him, assert it to be a rule that the presence of silica in the water is essential to the development of a geyser. In one sense this is true, and in another it is not. Should the heated waters find a ready-made tube, like a fissure in solid rock, this would serve for a geyser tube as well as any other. The Monarch Geyser, in Norris Geyser Basin, seems to have originated in this way. But in the general case, geyser tubes are built up, notfound ready made. In such cases silica is an indispensable ingredient of the water. A calcareous deposit, like that at Mammoth Hot Springs, would lack strength to resist the violent strain of an eruption. So it is found to be a fact that silica is the chief mineral ingredient in the water of all important geysers.
CHAPTER IV.
HOT SPRINGS.
Under this general head will be included all thermal phenomena of the Park, except the geysers. The term will cover the quiescent springs, the boiling springs, the mud springs, or “paint pots,” and the steam vents and fumaroles.
The quiescent spring seems to stand at the opposite pole from the geyser. The conditions are such that the water nowhere reaches a temperature sensibly above the boiling point. The surface therefore steams quietly away, unruffled except by the passing breeze.
The great attraction of these springs is in the inimitable coloring of the water. It is not simply the beautiful green or blue of great depths of clear water. In no ordinary pool can one find all the colors of the spectrum, flitting about, as though seen through a revolving prism. Sometimes there is an iridescent effect similar to that of a film of oil upon water; but there is no oil here. There are doubtless many contributing causes that produce these remarkable effects. There is first a great depth of clear water which always presents a beautiful appearance. Then there are the mineral deposits on the sides of the crater, producing indefinite reflection, the effects of which are multiplied by the refractive power of the water. The mineral ingredients dissolved or suspended in the water doubtless add to the effect.
The hot springs on the Gardiner River are whollydifferent in character from those in any other part of the Park. The water of these springs holds carbonate of lime in solution while most of the others contain silica. To this fact must be attributed the peculiar character of the formations at Mammoth Hot Springs. Wherever the deposits of springs are calcareous, the character of the formations is the same, and generally different from those produced by the deposit of silica. They rise in terraces one above another, and mold for themselves overhanging bowls of transcendent beauty in form and color. In the tints displayed by the water, however, these springs are not unlike others in the Park.
Terry Engr. Co.Haynes, Photo., St. Paul.Cleopatra Terrace.
Terry Engr. Co.
Haynes, Photo., St. Paul.
Cleopatra Terrace.
The rims about the quiescent springs are often very beautiful, and the observer is astonished to see how they stand up above the general surface of the ground so evenly built that the water has hardly a choice ofroute in flowing away. Tyndall, however, makes this puzzling phenomenon clear. He says:
“Imagine the case of a simple thermal siliceous spring, whose waters trickle down a gentle incline; the water thus exposed evaporates speedily, and silica is deposited. This deposit gradually elevates the side over which the water passes, until finally the latter has to take another course. The same takes place here; the ground is elevated as before, and the spring has to move forward. Thus it is compelled to travel round and round, discharging its silica and deepening the shaft in which it dwells, until finally, in the course of ages, the simple spring has produced that wonderful apparatus which has so long puzzled and astonished both the traveler and the philosopher.”
The boiling spring is intermediate between the quiescent spring and the geyser. The circulation is sufficiently free to prevent a great rise of temperature in the lower depths of the tube, and nothing more than a surface ebullition, often extremely violent, results. These springs are generally objects of secondary interest. They are simply enormous caldrons; any kettle placed over a brisk fire simulates their action on a small scale.
The mud springs, or Paint Pots, as they are now always called, are extremely curious phenomena. They are caused by the rising of steam through considerable depths of earthy material. The water is just sufficient in quantity to keep the material in a plastic condition, and the steam operates upon it precisely as it does upon a kettle of thick mush. Generally there are various mineral ingredients, mostly oxides of iron, which impart different colors to different parts of thegroup. As the steam puffs up here and there from the thick mass, it forms the mud into a variety of imitative figures, prominent among which is that of the lily. These figures immediately sink back into the general mass, only to be formed anew by other puffs of steam. The material is so fine as to be almost impalpable between the fingers. Lieutenant Doane, however, justly observes that “mortar might well be good after being constantly worked for perhaps ten thousand years.”
Other phenomena very common throughout the Park are steam vents or fumaroles in which there is no water or only a very small quantity. They are not ordinarily of much popular interest, although there are a few remarkable examples. Among these may be mentioned the Black Growler in the Norris Geyser Basin, and Steamboat Spring on the east shore of the Yellowstone Lake.
The hot spring areas of the Park are both numerous and extensive. They abound throughout the valleys of the Yellowstone, the Madison, and the Snake Rivers, and the number of individual springs is several thousand.
CHAPTER V.
FOSSIL FORESTS OF THE YELLOWSTONE.
A region of great popular and scientific interest in the Yellowstone Park, although as yet hardly known to the tourist, owing to the incomplete condition of the road system, is that of the Fossil Forests in the north-east corner of the Park. The facts which have been brought to light concerning the origin of these forests are worthy of particular consideration.
The trees are found to occur in different planes or horizons of growth, one above another, until the whole series represents a thickness of many hundreds, and possibly thousands, of feet. Going back to the first of these growths, it is found to have been destroyed by an outpouring of volcanic material, which partially or wholly submerged it. After the flow had ceased, the ordinary atmospheric and aqueous agencies began work, eroding the surface in some places and depositing the products of erosion in others, while vegetation rapidly covered the newly-formed soil. A subsequent flow destroyed this second growth and gave a new horizon, on which the same process was repeated. This continued until there were at least nine, and probably twelve, of these consecutive growths.