Chapter VIII: Part 8

In addition to these, during the week preceding the 27th Professor McClure made numerous observations both of pressure and temperature at various sub-stations in the vicinity of Mount Rainier, and simultaneous observations are furnished from Seattle and Portland.

At the very outset of the work of reduction it was evident that Eugene and Roseburg were under an area of relatively low barometric pressure on the 27th, representing atmospheric conditions that did not prevail in the region of Mount Rainier. I therefore rejected the observations at both these places, using only those at Seattle, Portland, Fort Canby and Walla Walla. The strategic position of these four points will be seen at once by a glance at the map.

The method followed in making the reduction was, in brief, to deduce from the observations at the four base stations surrounding the mountain the actual atmospheric conditions prevailing in the immediate region of the mountain. More specifically, the process consisted in determining the atmospheric pressure and temperature at an imaginary sea level vertically under the mountain, which level I shall subsequently call the "mean base."

In this I was greatly assisted by a careful study of the daily weather charts issued by the government, Mr. Pague having kindly loaned me his official file for July. I thus practically had at my disposal observations from all the important points on the Coast, both before and after the principal observation. With due regard to the position and direction of the isobars, and giving proper weight to the observations at each of the four base stations, I finally deduced 30.130 inches as the value of the pressure at the mean base which best satisfied all the data. It ought to be said, perhaps, that this result does not depend upon my judgment to any appreciable extent, but was legitimately worked out from the observations and isobaric lines.

In determining the mean temperature of the air column extending from the mean base to the summit of the mountain, the observations made by Professor McClure during the previous week in the vicinity were so numerous and well timed as to leave far less than the usual amount of uncertainty. Making due allowance for the moderate elevations of the stations, these observations show clearly that the temperature about the mountain at that time followed that of Seattle very closely, and was also not much different from that of Portland, but departed notably from both the heat of Walla Walla and the low temperature of Fort Canby. Allowing proper weight to these facts, the observations at the base stations, with that of Professor McClure at the summit, gave 49 degrees Fahrenheit as the mean temperature of the air column.

I regard the method of reduction outlined above as possessing decided advantages over any other that could be applied to the problem in hand; especially because it admits of using the isobaric charts with great freedom and effectiveness, thereby increasing the reliability of the result to a marked extent.

The reduction made, there remained for the final calculation the following data:

Barometric pressure at the summit of Rainier 17.708 inches
Barometric pressure at mean base 30.130 inches
Mean temperature of air column 49 deg. F.
Latitude of Mount Rainer 46 deg. 48 min.

In making the calculation I used the amplified form of Laplace's formula given in the recent publications of the Smithsonian Institution, with the constants there adopted. Perhaps for the general reader it may be important to remark that this formula, besides the barometric pressures, contains corrections for the temperature of the air column; for latitude, and for the variation of gravity with altitude in its effect on the weight of the mercury in the barometer; for the average humidity of the air; and for the variation of gravity with altitude in its effect on the weight of the air. I used the latest edition of the Smithsonian tables, but afterward verified the result by a numerical solution of the formula--the altitude being, as stated at the beginning, 14,528 feet above sea level.

It should be noted as an evidence of the great care and foresight with which Professor McClure planned his work and the success with which he carried it out, that the result of his observations agrees within nine feet with that obtained by the United States Geological Survey in 1895, using, as we may suppose, the most refined methods of triangulation--the latter estimate being 14,519 feet. In connection with so great an altitude, nine feet is an insignificant quantity, and the close correspondence in the results of the two methods of measurement is truly remarkable. I am not inclined to regard it as accidental, but as due to the most careful work in both cases.

Having a full knowledge of all the available data, I am perhaps better prepared than anyone else to pass judgment upon the result set forth; and while it would be folly to give a numerical estimate of the probable error, I feel justified in saying that no single barometric determination is ever likely to prove more accurate than this one of Professor McClure's. At any rate, the outstanding error is now too small to justify the hazard of any future attempts.

From the observations made by Professor McClure while en route to the summit, together with simultaneous records from Seattle and Portland, the following altitudes are obtained:

FEET ABOVE SEA LEVEL
Eatonville 870
Kernahan's ranch 1,880
Longmire springs 2,850
Mazama camp 5,932
Camp-No-Camp 12,700
South side Crater Rainier 14,275

The data in these cases were not sufficient to admit an elaborate working-out of the altitude, so that the figures given are to be regarded as rather close approximations, except in the case of Mazama camp, the altitude of which rests upon four observations and is correspondingly reliable.

Professor McClure's barometer had a notable history in mountaineering. To quote the professor's own words:

"It has twice looked upon the beauties of the Columbia river from the summit of Mount Hood. It was the first barometer taken to the top of Mount Hood, and gave the true elevation, 11,225 feet, in place of 17,000 or 18,000 feet previously claimed. This barometric measurement of Mount Hood was made in August, 1867, by a government party under the direction of Lieutenant R. S. Williamson. The second barometric measurement of Mount Hood was made with the same instrument in August, 1870, by Professor George H. Collier."

In August, 1891, the barometer was carried by Professor McClure to the summit of Diamond Peak; in August, 1894, by the writer, to the summit of the middle peak of the Three Sisters, in Oregon, giving an altitude of 10,080 feet, not hitherto published; in July, 1895, Professor McClure took it with the Mazamas to Mount Adams, and in July, 1897, to the summit of Mount Rainier.

A new tube was filled and inserted about two years ago, Professor McClure preparing the mercury by distillation and the writer boiling it in the tube. The vacuum was exceptionally perfect. The comparison sheet previously mentioned showed that the instrument on the occasion of its last trip read .005 inch above standard.

In thus completing the labors of Professor McClure, with whom I was so long and so intimately associated, I feel a very melancholy satisfaction. For his sake, I have spared no pains in collecting all the useful data that could be obtained, to make the result reliable to the last degree possible in such a case. I leave that result as a sufficient guarantee of the accuracy of the whole work from beginning to end.

XIII. FIELD NOTES ON MOUNT RAINIER, 1905

BY PROFESSOR HENRY LANDES

Henry Landes is Professor of Geology and Dean of the College
of Science, University of Washington, and he has also served
as State Geologist of Washington, since 1895. He was born at
Carroll, Indiana, on December 22, 1867. He graduated from the
University of Indiana in 1892 and obtained the Master of Arts
degree at Harvard University in 1893. He was assistant to the
State Geologist of New Jersey and Principal of the High
School at Rockland, Maine, before being elected to his
present professorship at the University of Washington in
1895. For a year and a half, 1914-1915, he was Acting
President of the University of Washington.

He has published many articles and pamphlets on geological
subjects. The one here given appeared in Mazama, published in
December, 1905, by the Mazamas in Portland, Oregon. It is
reproduced here with the permission of the author and of the
mountaineering club.

The Columbia River afforded to the first people who came to Washington and Oregon the easiest and most feasible route across the Cascade Mountains. It was through this gateway that travel passed from one side of the range to the other until the advent of the railways in comparatively recent years. The early travelers along the river who were of an observing or scientific bent, noted that the rocks were, in general, dark, heavy and massive and of the class commonly known as basalt. Here and there a sort of pudding stone or agglomerate was observed, which in some instances might represent a sedimentary deposit, but which here had clearly an igneous origin.

The observations of the early travelers were supplemented later by the further studies of geologists; and from the facts noted along the Columbia River, the generalization holds good to a great extent on the Oregon side, but it is by no means true on the Washington side, as has been shown by later studies. Granite rocks are encountered within a few miles of the Columbia River as one travels north along the Cascade Range. Associated with these granite rocks are found rocks of a metamorphic type, such as gneiss, schists, quartzites, crystalline limestone, slate, etc. Such rocks exist south of Mount Rainier, but are not conspicuous. North of this point, however, and throughout all of the northern Cascades they form the great bulk of the rock.

In other words, in the Cascades of Washington, igneous activity has been much more common in the region south of Rainier than in that north of the mountain. When the first observations were made upon the great lava flows of southeastern Washington, which form a part of the greatest lava plain in the world, it was supposed that the lava had its origin in the volcanoes of the Cascades. Later investigations have shown this view to be erroneous. The lava of the plain has come directly from below through great longitudinal fissures instead of through circular openings such as one finds in volcanoes.

It is probable that the Cascades, like most other mountains, have had several different periods of uplift. We have several notable examples of mountains which have had an initial uplift and then have been reduced to base by erosion. By a second upheaval the plain has been converted into a plateau, and this in time assumes a very rugged, mountainous character as a result of the combined forces of air and water. Eventually these same forces would reduce the region to a plain again. Just how many times this thing has happened in the Cascades we do not know. Bailey Willis has shown that in the northern Cascades, at least, the whole country was reduced to a plain prior to the last uplift, which took place in comparatively recent times. Out of this plateau, formed by the uplifting of the plain, has arisen through the active attack of erosive forces the truly mountainous character of the district. Erosion has been at the maximum in the mountains because of the heavy precipitation. Precipitation in the high mountains being chiefly in the form of snow has led to the formation of glaciers, producing thereby a rapidity of erosion of the first order. The active work of ice and running water has given to the mountains an extremely rugged appearance, characterized by valleys of great depth extending into the very heart of the mountains and with precipitous divides.

It must be understood that the time consumed in the uplifting of the Cascades, and the conversion from plain to plateau, was of considerable duration. With the beginning of the uplift, the sluggish streams of the plain became rejuvenated, and took up actively once more the work of erosion. By the time the maximum uplift was reached, the plateau had lost to a certain degree its character of extreme levelness. The streams had already entrenched themselves in rather conspicuous valleys. It is believed that the great volcanoes of Washington--Rainier and its associates--began their activities about the time the uplift described above reached its maximum height. In the vicinity of Rainier the rock of the old plateau is granite; and the volcano may be said to be built upon a platform of that material. On the north side of the mountain granite appears conspicuously at a height of about 7,000 feet; while on the south side it appears at points varying from 5,000 to 6,000 feet above the sea.

That the surface of the granite platform was irregular and uneven may be seen in the walls of the Nisqually canyon, near the lower terminus of the glacier. As one ascends the canyon to the glacier, the contact between the lava rock and the granite shows quite plainly on both the right and the left side. On the left the contact is at least 1,000 feet above that on the right side. A little way above the lower end of the glacier, on each side of the canyon, a good opportunity presents itself to study the contact of the lava and granite. The granite at this place shows clearly that it was once a land surface; and one may note weathering for a distance downward of seventy-five or one hundred feet. The upper portion of the granite shows the usual characteristics of weathering, namely, the conversion of feldspar into kaolin, the oxidation of iron, etc. At this point the lava overlying the granite is quite basic and massive. The first flow reached a thickness here of fully three hundred feet, and exhibits a fine development of basaltic structure.

In following up the canyon walls one observes that the activity of the volcano for some time was characterized almost exclusively by lava flows. In the main the lava is an andesite, and is very generally of a porphyritic structure. Some of the lava flows were of great extent, and reached points many miles distant from the center of the mountain. While the earlier stages of the activity of the volcano were characterized by lava flows of great thickness, by and by explosive products began to appear, and interbedded with the sheets of lava one finds bombs, lapilli, cinders, etc.

It may be said in general that as the volcano grew in years it changed more and more from eruptions of the quiet type to those of the explosive character. It is plain that a long period of time was consumed in the making of that great volcanic pile, and that the eruptions were by no means continuous. It is clearly shown that after certain outflows of lava, quietude reigned for a time; that at last the surface of the rock became cool and that erosive agents broke it up into great masses of loose stones. In later flows of lava these stones were picked up and cemented into layers of pudding stone, which are styled agglomerates.

Rocks of an agglomerate type are well shown in the walls of Gibraltar. This massive pile is largely made up of boulders, great and small, rather loosely held together by a lava cement. The work of frost and ice, expansion and contraction, loosens the boulders readily, and their constant falling from the cliffs gives to this part of the mountain's ascent its dangerous character. While this volcano belongs to a very late period in the history of the earth, it is very clear that there has been no marked activity for many thousands of years. The presence of steam, which is emitted from the hundreds of small openings about the crater, undoubtedly shows the presence of heated rock at no great distance below the surface. Rock is a poor conductor, however, and cooling takes place with very great slowness after a depth of comparatively few feet is reached.

Like most volcanoes, the composite character of the cone is shown on Mount Rainier. After a certain height is reached in the building up of a cone, the rising lava in the throat, or the explosive activities within, sometimes produce an opening through the walls of the cone, and a new outlet to the surface is formed. This often gives the volcano a sort of hummocky or warty appearance, and produces a departure from the symmetrical character. In the case of Rainier it seems to the writer that upon the summit four distinct craters, or outlets, are distinguishable. The first crater reached by the usual route of ascent is the largest one, and may be styled the East crater. It is nearly circular in outline, with a diameter of about one-half mile. Its walls are bare of snow for nearly the whole of its circumference, but the pit is filled with snow and ice. Going across the crater to the westward, one passes over what is really the highest point on the mountain, and then goes down into a smaller crater, or the West crater. This is similar in character and outline to its neighbor, but here the many jets of issuing steam are much more prominent. At a point a few hundred feet lower on the mountain-side there is a peak known as Liberty Cap. A cross-section of the cap is in plain view and shows very clearly that this is a minor cone or local point of eruption. It is made up of rock very similar to the main mass of the mountain; and it is likely that the volcanic activity of the mountain was centered here for some time. Looking directly south from the West crater one sees at a distance of less than a mile another peak which is entirely snow-covered; but which may represent an instance parallel with that of the peak on the north side.

Mount Rainier is so deeply covered with ice and snow that the glacial aspects of the mountain are far more conspicuous than the volcanic ones. The facts about the vulcanism and the history of the growth of the mountain are very difficult to study; and it will be a long time before they are fully known. The glaciers, on the other hand, are very conspicuous, comparatively easy of access, and the many facts concerning their extent, rate of motion, recession, or advance, may be quite readily determined. The glaciers, while very prominent at the present time, were at one time much larger than now. There are many things which go to prove that they formerly reached much farther down the valleys.

From the top of the mountain one may see off to the westward for many miles south of Puget Sound prairies of large size, covering a great many square miles. These prairies represent the plains of gravel derived from the melting glaciers, when these stood in their vicinity. From these points of maximum extension the glaciers have slowly receded to their present position.

That the glaciers are receding at the present time is a matter of common observation. At the lower end of the Nisqually glacier the advancing line of vegetation is about one-fourth mile below the present limit of the ice. It is the opinion of Mr. Longmire that the glacier has retreated about that far since he first came to the valley, twenty-five years ago. General Stevens was able to point out several instances of notable shrinkages in the glaciers, especially in the Paradise glacier, since his ascent of the mountain in 1870. It will interest students of glaciers to know that some permanent monuments have been set up at the lower end of the Nisqually glacier; and that arrangements have been made whereby the retreat of the ice may be accurately measured from year to year.

XIV. GLACIERS OF MOUNT RAINIER

BY F. E. MATTHES

François Émile Matthes was born at Amsterdam, Holland, on
March 16, 1874. After pursuing studies in Holland,
Switzerland and Germany, he came to the United States in 1891
and graduated from the Massachusetts Institute of Technology
in 1895. Since 1896 he has been at work with the United
States Geological Survey, mostly in the field of topography.
He has been honored by and is a member of many scientific
societies.

His topographic work on the maps of Yosemite and Mount
Rainier National Parks made for him many appreciative friends
on the Pacific Coast. His pamphlet on "Mount Rainier and Its
Glaciers" was published by the United States Department of
the Interior in 1914. He secured consent for its
republication in the present work.

The impression still prevails in many quarters that true glaciers, such as are found in the Swiss Alps, do not exist within the confines of the United States, and that to behold one of these rare scenic features one must go to Switzerland, or else to the less accessible Canadian Rockies or the inhospitable Alaskan coast. As a matter of fact, permanent bodies of snow and ice, large enough to deserve the name of glaciers, occur on many of our western mountain chains, notably in the Rocky Mountains, where only recently a national reservation--Glacier National Park--was named for its ice fields; in the Sierra Nevada of California, and farther north, in the Cascade Range. It is on the last-named mountain chain that glaciers especially abound, clustering as a rule in groups about the higher summits of the crest. But this range also supports a series of huge, extinct volcanoes that tower high above its sky line in the form of isolated cones. On these the snows lie deepest and the glaciers reach their grandest development. Ice clad from head to foot the year round, these giant peaks have become known the country over as the noblest landmarks of the Pacific Northwest. Foremost among them are Mount Shasta, in California (14,162 feet); Mount Hood, in Oregon (11,225 feet); Mount St. Helens (9,697 feet), Mount Adams (12,307 feet), Mount Rainier (14,408 feet), and Mount Baker (10,730 feet), in the State of Washington.

Easily king of all is Mount Rainier. Almost 250 feet higher than Mount Shasta, its nearest rival in grandeur and in mass, it is overwhelmingly impressive, both by the vastness of its glacial mantle and by the striking sculpture of its cliffs. The total area of its glaciers amounts to no less than 45 square miles, an expanse of ice far exceeding that of any other single peak in the United States. Many of its individual ice streams are between 4 and 6 miles long and vie in magnitude and in splendor with the most boasted glaciers of the Alps. Cascading from the summit in all directions, they radiate like the arms of a great starfish. All reach down to the foot of the mountain and some advance considerably beyond.

As for the plea that these glaciers lie in a scarcely opened, out-of-the-way region, a forbidding wilderness as compared with maturely civilized Switzerland, it no longer has the force it once possessed. Rainier's ice fields can now be reached from Seattle or Tacoma, the two principal cities of western Washington, in a comfortable day's journeying, either by rail or by automobile. The cooling sight of crevassed glaciers and the exhilarating flower-scented air of alpine meadows need no longer be exclusive pleasures, to be gained only by a trip abroad.

Mount Rainier stands on the west edge of the Cascade Range, overlooking the lowlands that stretch to Puget Sound. Seen from Seattle or Tacoma, 60 and 50 miles distant, respectively, it appears to rise directly from sea level, so insignificant seem the ridges about its base. Yet these ridges themselves are of no mean height. They rise 3,000 to 4,000 feet above the valleys that cut through them, and their crests average 6,000 feet in altitude. Thus at the southwest entrance of the park, in the Nisqually Valley, the elevation above sea level, as determined by accurate spirit leveling, is 2,003 feet, while Mount Wow (Goat Mountain), immediately to the north, rises to an altitude of 6,045 feet. But so colossal are the proportions of the great volcano that they dwarf even mountains of this size and give them the appearance of mere foothills. In the Tatoosh Range Pinnacle Peak is one of the higher summits, 6,562 feet in altitude. That peak rises nearly 4,000 feet above the Nisqually River, which at Longmire has an elevation of 2,700 feet, yet it will be seen that Mount Rainier towers still 7,846 feet higher than Pinnacle Peak.

From the top of the volcano one fairly looks down upon the Tatoosh Range, to the south; upon Mount Wow, to the southwest; upon the Mother Mountains, to the northwest, indeed, upon all the ridges of the Cascade Range. Only Mount Adams, Mount St. Helens, and Mount Hood loom like solitary peaks above the even sky line, while the ridges below this line seem to melt together in one vast, continuous mountain platform. And such a platform, indeed, one should conceive the Cascade Range once to have been. Only it is now thoroughly dissected by profound, ramifying valleys, and has been resolved into a sea of wavelike crests and peaks.

Mount Rainier stands, in round numbers, 10,000 feet high above its immediate base, and covers 100 square miles of territory, or one-third of the area of Mount Rainier National Park. In shape it is not a simple cone tapering to a slender, pointed summit like Fuji Yama, the great volcano of Japan. It is, rather, a broadly truncated mass resembling an enormous tree stump with spreading base and irregularly broken top. Its life history has been a varied one. Like all volcanoes, Rainier has built up its cone with the material ejected by its own eruptions--with cinders and bombs (steam-shredded particles and lumps of lava), and with occasional flows of liquid lava that have solidified into layers of hard, basaltic rock. At one time it attained an altitude of not less than 16,000 feet, if one may judge by the steep inclination of the lava and cinder layers visible in its flanks. Then a great explosion followed that destroyed the top part of the mountain, and reduced its height by some 2,000 feet. The volcano was left beheaded, and with a capacious hollow crater, surrounded by a jagged rim.

Later on this great cavity, which measured nearly 3 miles across, from south to north, was filled by two small cinder cones. Successive feeble eruptions added to their height until at last they formed together a low, rounded dome--the eminence that now constitutes the mountain's summit. It rises only about 400 feet above the rim of the old crater, and is an inconspicuous feature, not readily identifiable from all sides as the highest point. In fact, so broad is the mountain's crown that from no point at its base can one see the top. The higher portions of the old crater rim, moreover, rise to elevations within a few hundred feet of the summit, and, especially when viewed from below, stand out boldly as separate peaks that mask and seem to overshadow the central dome. Especially prominent are Peak Success (14,150 feet) on the southwest side, and Liberty Cap (14,112 feet) on the northwest side.

The altitude of the main summit has for many years been in doubt. Several figures have been announced from time to time, no two of them in agreement with each other; but all of these, it is to be observed, were obtained by more or less approximate methods. In 1913 the United States Geological Survey, in connection with its topographic surveys of the Mount Rainier National Park, was able to make a new series of measurements by triangulation methods at close range. These give the peak an elevation of 14,408 feet, thus placing it near the top of the list of high summits of the United States. This last figure, it should be added, is not likely to be in error by more than a foot or two and may with some confidence be regarded as final. Greater exactness of determination is scarcely practicable in the case of Mount Rainier, as its highest summit consists actually of a mound of snow the height of which naturally varies somewhat with the seasons and from year to year.

This crowning snow mound, which was once supposed to be the highest point in the United States, still bears the proud name of Columbia Crest. It is essentially a huge snowdrift or snow dune, heaped up by the westerly winds. Driving furiously up through the great breach in the west flank of the mountain, between Peak Success and Liberty Cap, they eddy lightly as they shoot over the summit and there deposit their load of snow.

The drift is situated at the point where the rims of the two summit craters touch, and represents the only permanent snow mass on these rims, for some of the internal heat of the volcano still remains and suffices to keep these rock-crowned curving ridges bare of snow the better part of the year. It is intense enough, even, to produce numerous steam jets along the inner face of the rim of the east crater, which appears to be the most recently formed of the two. The center of this depression, however, is filled with snow, so that it has the appearance of a shallow, white-floored bowl some 1,200 feet in diameter. Great caverns are melted out by the steam jets under the edges of the snow mass, and these caverns afford shelters which, though uninviting, are not to be despised. They have proved a blessing to more than one party that has found itself compelled to remain overnight on the summit, saving them from death in the icy gales.

That Mount Rainier should still retain so much of its internal heat is not surprising in view of the recency of its eruptions. It is known to have been active at intervals during the last century, and actual record exists of slight eruptions in 1843, 1854, 1858, and 1870. Indian legends mention a great cataclysmal outburst at an earlier period.

At present the volcano may be regarded as dormant and no apprehension need be felt as to the possibility of an early renewal of its activity. The steam jets in the summit crater, it is true, as well as the hot springs at the mountain's foot (Longmire Springs), attest the continued presence of subterranean fires, but they are only feeble evidences as compared with the geysers, the steam jets, and the hot springs of the Yellowstone National Park. Yet that region is not considered any less safe to visit because of the presence of these thermal phenomena.

In spite of Mount Rainier's continued activity until within the memory of man its sides appear to have been snow clad for a considerable length of time. Indeed, so intense and so long-continued has been the eroding action of the ice that the cone is now deeply ice-scarred and furrowed. Most of its outer layers, in fact, appear already to have been stripped away. Here and there portions of them remain standing on the mountain's flanks in the form of sharp-crested crags and ridges, and from these one may roughly surmise the original dimensions of the cone. Mere details in the volcano's sculpture, these residual masses are, some of them, so tall that, were they standing among ordinary mountains, they would be reckoned as great peaks. Particularly noteworthy is Little Tahoma, a sharp, triangular tooth on the east flank, that rises to an elevation of 11,117 feet. In its steep, ice-carved walls one may trace ascending volcanic strata aggregating 2,000 feet in thickness that point upward to the place of their origin, the former summit of the mountain, which rose almost half a mile higher than the present top.

Nor is the great crater rim left by the explosion that carried off the original summit preserved in its entirety. Peak Success and Liberty Cap are the only two promontories that give trustworthy indication of its former height and strength. Probably they represent the more massive portions on the southwest and northwest sides, respectively, while the weaker portions to the east and south have long since crumbled away under the heavy ice cascades that have been overriding them for ages. Only a few small rocky points remain upon which the snows split in their descent. The most prominent, as well as the most interesting, is the one on the southeast side, popularly known as Gibraltar Rock. Really a narrow, wedge-shaped mass, it appears in profile like a massive, square-cut promontory. The trail to the summit of the mountain passes along its overhanging south face and then ascends by a precipitous chute between ice and rock. It is this part of the ascent that is reputed as the most precarious and hazardous.

From the rim points downward the ice cover of the cone divides into a number of distinct stream-like tongues or glaciers, each sunk in a great hollow pathway of its own. Between these ice-worn trenches the uneroded portions of the cone stand out in high relief, forming as a rule huge triangular "wedges," heading at the sharp rim points and spreading thence downward to the mountain's base. There they assume the aspect of more gently sloping, grassy table-lands, the charming alpine meadows of which Paradise Park and Spray Park are the most famous. Separating these upland parks are the profound ice-cut canyons which, beyond the glacier ends, widen out into densely forested valleys, each containing a swift-flowing river. No less than a dozen of these ice-fed torrents radiate from the volcano in all directions, while numerous lesser streams course from the snow fields between the glaciers.

Thus the cone of Mount Rainier is seen to be dissected from its summit to its foot. Sculptured by its own glacier mantle, its slopes have become diversified with a fretwork of ridges, peaks, and canyons.

The first ice one meets on approaching the mountain from Longmire Springs lies in the upper end of the Nisqually Valley. The wagon road, which up to this point follows the west side of the valley, winding in loops and curves along the heavily wooded mountain flank, here ventures out upon the rough bowlder bed of the Nisqually River and crosses the foaming torrent on a picturesque wooden bridge. A scant thousand feet above this structure, blocking the valley to a height of some 400 feet, looms a huge shapeless pile of what seems at first sight only rock débris, gray and chocolate in color. It is the dirt-stained end of one of the largest glaciers--the Nisqually. From a yawning cave in its front issues the Nisqually stream, a river full fledged from the start.

The altitude here, it should be noted, is a trifle under 4,000 feet (elevation of bridge is 3,960 feet); hence the ice in view lies more than 10,000 feet below the summit of the mountain, the place of its origin. And in this statement is strikingly summed up the whole nature and economy of a glacier such as the Nisqually.

A glacier is not a mere stationary blanket of snow and ice clinging inert to the mountain flank. It is a slowly moving streamlike body that descends by virtue of its own weight. The upper parts are continually being replenished by fresh snowfalls, which at those high altitudes do not entirely melt away in summer; while the lower end, projecting as it does below the snow line, loses annually more by melting than it receives by precipitation, and is maintained only by the continued accession of masses from above. The rate at which the ice advances has been determined by Prof. J. N. Le Conte, of the University of California. In 1903 he placed a row of stakes across the glacier, and with the aid of surveying instruments obtained accurate measurements of the distances through which they moved from day to day. He found that in summer, when the movement is greatest, it averages 16 inches per day. This figure, however, applies only to the central portion of the glacier--the main current, so to speak--for the margins necessarily move more slowly, being retarded by friction against the channel sides.

The snout of the Nisqually Glacier, accordingly, is really composed of slowly advancing ice, but so rapid is the melting at this low altitude that it effectually counterbalances the advance, and thus the ice front remains essentially stationary and apparently fixed in place. Actually, it is subject to slight back and forward movements, amounting to a foot or more per day; for, as one may readily imagine, fluctuations in snowfall and in temperature, above or below the normal, are ever likely to throw the balance one way or another.

A glacier may also make periodic advances or retreats on a larger scale in obedience to climatic changes extending over many years. Thus all the glaciers on Mount Rainier, as well as many in other parts of the world, are at present, and have been for some time, steadily retreating as the result of milder climate or of a lessening in snow supply. Only so recently as 1885 the Nisqually Glacier reached down to the place now occupied by the bridge, and it is safe to say that at that time no engineer would have had the daring to plan the road as it is now laid. In the last 25 years, however, the Nisqually Glacier has retreated fully 1,000 feet.

Evidences of similar wholesale recession are to be observed at the ends of the other glaciers of Mount Rainier, but the measure of their retreat is not recorded with the precision that was possible in the case of the Nisqually Glacier. Eyewitnesses still live at Longmire Springs who can testify to the former extension of the Nisqually Glacier down to the site of the wagon bridge.

As one continues the ascent by the wagon road a partial view of the glacier's lower course is obtained, and there is gained some idea of its stream-like character. More satisfying are the views from Paradise Park. Here several miles of the ice stream (its total length is nearly 5 miles) lie stretched out at one's feet, while looking up toward the mountain one beholds the tributary ice fields and ice streams, pouring, as it were, from above, from right and left, rent by innumerable crevasses and resembling foaming cascades suddenly crystallized in place. The turmoil of these upper branches may be too confusing to be studied with profit, but the more placid lower course presents a favorable field for observation, and a readily accessible one at that.

A veritable frozen river it seems, flowing between smooth, parallel banks, half a mile apart. Its surface, in contrast to the glistening ice cascades above, has the prevailingly somber tint of old ice, relieved here and there by bright patches of last winter's snow. These lie for the most part in gaping fissures or crevasses that run athwart the glacier at short intervals and divide its body into narrow slices. In the upper course, where the glacier overrides obstacles in its bed, the crevasses are particularly numerous and irregularly spaced, sometimes occurring in two sets intersecting at right angles, and producing square-cut prisms. Farther down the ice stream's current is more sluggish and the crevasses heal up by degrees, providing a united surface, over which one may travel freely.

Gradually, also, the glacier covers itself with débris. Angular rock fragments, large and small, and quantities of dust, derived from the rock walls bordering the ice stream higher up, litter its surface and hide the color of the ice. At first only a narrow ridge of such material--a moraine, as it is called--accompanies the ice river on each side, resembling a sharp-crested embankment built by human hands to restrain its floods; but toward the lower end of the glacier, as the ice wastes away, the débris contained in it is released in masses, and forms brown marginal bands, fringing the moraines. In fact, from here on down it becomes difficult to tell where the ice of the glacier ends at the sides and where the moraines begin.

The lower part of the glacier also possesses a peculiar feature in the form of a débris ridge about midway on its back--a medial moraine. Most of the way it stretches like a slender, dark ribbon, gradually narrowing upstream. One may trace it with the eye up to its point of origin, the junction of the two main branches of the glacier, at the foot of a sharp rock spur on the mountain's flank.

In the last mile of the Nisqually's course, this medial moraine develops from a mere dirt band to a conspicuous embankment, projecting 40 feet above the ice. Not the entire body of the ridge, however, is made up of rock débris. The feature owes its elevation chiefly to the protective influence of the débris layer on its surface, which is thick enough to shield the ice beneath from the hot rays of the sun, and greatly retards melting, while the adjoining unprotected ice surfaces are rapidly reduced.

A short distance above the glacier's terminus the medial moraine and the ever-broadening marginal bands come together. No more clear ice remains exposed, irregular mounds and ridges of débris cover the entire surface of the glacier, and the moraine-smothered mass assumes the peculiar inchoate appearance that is so striking upon first view.

In utter contrast with the glacier's dying lower end are the bright snow fields on the summit in which it commences its career. Hard by the rock rim of the east summit crater the snows begin, enwrapping in an even, immaculate layer the smooth sides of the cinder cone. Only a few feet deep at first, they thicken downward by degrees, until, a thousand feet below the crater, they possess sufficient depth and weight to acquire movement. Occasional angular crevasses here interrupt the slope and force the summit-bound traveler to make wearying detours.

Looking down into a gash of this sort one beholds nothing but clean snow, piled in many layers. Only a faint blue tinges the crevasse walls, darkening but slowly with the depth, in contrast to the intense indigo hue characteristic of the partings in the lower course of the glacier. There the material is a dense ice, more or less crystalline in texture; here it is scarcely more than snow, but slightly compacted and loosely granular--what is generally designated by the Swiss term "névé."

For several thousand feet down, as far as the 10,000-foot level, in fact, does the snow retain this granular consistency. One reason for the slowness with which it compacts is found in the low temperatures that prevail at high altitudes and preclude any considerable melting. The air itself seldom rises above the freezing point, even in the middle of the day, and as a consequence the snow never becomes soft and mushy, as it does at lower levels.

When snow assumes the mushy, "wet-sugar" state, it is melting internally as well as at its outer surface, owing both to the water that soaks into it and to the warming of the air inclosed within its innumerable tiny pores (which tiny air spaces, by the way, give the snow its brilliant whiteness). Snow in this condition has, paradoxical though it may sound, a temperature a few tenths of a degree higher than the melting point--a fact recently established by delicate temperature measurements made on European glaciers. It is this singular fact, no doubt, that explains how so many minute organisms are able to flourish and propagate in summer on the lower portions of many glaciers. It may be of interest to digress here briefly in order to speak of these little known though common forms of life.

Several species of insects are among the regular inhabitants of glaciers. Most of them belong to a very low order--the Springtails, or _Thysanura_--and are so minute that in spite of their dark color they escape the attention of most passers-by. If one looks closely, however, they may readily be observed hopping about like miniature fleas or wriggling deftly into the cavities of the snow. It seems to incommode them but little if in their acrobatic jumps they occasionally alight in a puddle or in a rill, for they are thickly clad with furry scales that prevent them from getting wet--just as a duck is kept dry by its greasy feathers.

Especially plentiful on the lower parts of the Rainier glaciers, and more readily recognized, are slender dark-brown worms of the genus _Mesenchytraeus_, about 1 inch in length. Millions and millions of them may be seen on favorable days in July and August writhing on the surface of the ice, evidently breeding there and feeding on organic matter blown upon the glacier in the form of dust. So essential to their existence is the chill of the ice that they enter several inches, and sometimes many feet below the surface on days when the sun is particularly hot, reappearing late in the afternoon.

Mention also deserves to be made of that microscopic plant _Protococcus nivalis_, which is responsible for the mysterious pink or light, rose-colored patches so often met with on glaciers--the "red snow" of a former superstition. Each patch represents a colony or culture comprising billions of individuals. It is probable that they represent but a small fraction of the total microflora thriving on the snow, the other species remaining invisible for lack of a conspicuous color.

To return to the frigid upper névés, it is not to be supposed that they suffer no loss whatever by melting. The heat radiated directly to them by the sun is alone capable of doing considerable damage, even while the air remains below the freezing point. At these high altitudes the sun heat is astonishingly intense, as more than one uninitiated mountain climber has learned to his sorrow by neglecting to take the customary precaution of blacking his face before making the ascent. In a few hours the skin is literally scorched and begins to blister painfully.

At the foot of the mountain the sun heat is relatively feeble, for much of it is absorbed by the dust and vapor in the lower layers of the atmosphere, but on the summit, which projects 2 miles higher, the air is thin and pure, and lets the rays pass through but little diminished in strength.

The manner in which the sun affects the snow is peculiar and distinctive. Instead of reducing the surface evenly, it melts out many close-set cups and hollows, a foot or more in diameter and separated by sharp spires and crests. No water is visible anywhere, either in rills or in pools, evaporation keeping pace with the reduction. If the sun's action is permitted to continue uninterrupted for many days, as may happen in a hot, dry summer, these snow cups deepen by degrees, until at length they assume the aspect of gigantic bee cells, several feet in depth. Snow fields thus honeycombed may be met with on the slopes above Gibraltar Rock. They are wearisome to traverse, for the ridges and spines are fairly resistant, so that one must laboriously clamber over them. Most exasperating, however, is the going after a snowstorm has filled the honeycombs. Then the traveler, waist deep in mealy snow, is left to flounder haphazard through a hidden labyrinth.

Of interest in this connection is the great snow cliff immediately west of Gibraltar Rock. Viewed from the foot of that promontory, the sky line of the snow castle fairly bristles with honeycomb spines; while below, in the face of the snow cliff, dark, wavy lines, roughly parallel to the upper surface, repeat its pattern in subdued form. They represent the honeycombs of previous seasons, now buried under many feet of snow, but still traceable by the dust that was imprisoned with them.

The snow cliff west of Gibraltar Rock is of interest also for other reasons. It is the end of a great snow cascade that descends from the rim of the old crater. Several such cascades may be seen on the south side of the mountain, separated by craggy remnants of the crater rim. Above them the summit névés stretch in continuous fields, but from the rim on down, the volcano's slopes are too precipitous to permit a gradual descent, and the névés break into wild cascades and falls. Fully two to three thousand feet they tumble, assembling again in compact, sluggish ice fields on the gentler slopes below.

Of the three cascades that feed the Nisqually Glacier only the central one, it is to be observed, forms a continuous connection between the summit névés and the lower ice fields. The two others, viz. the one next to Gibraltar and the westernmost of the three, terminate in vertical cliffs, over great precipices of rock. From them snow masses detach at intervals and produce thundering avalanches that bound far out over the inclined ice fields below. Especially frequent are the falls from the cliff near Gibraltar. They occur hourly at certain times, but as a rule at periods of one or more days.

From the westernmost cascade avalanches are small and rare. Indeed, as one watches them take place at long intervals throughout a summer one can not but begin to doubt whether they are in themselves really sufficient to feed and maintain so extensive an ice field as lies stretched out under them. Surely much more snow must annually melt away from the broad surface of that field, exposed as it lies to the midday sun, than the insignificant avalanches can replace. Were they its only source of supply, the ice field, one feels confident, would soon cease to exist.

The fact is that the ice field in question is not dependent for its support on the avalanches from above. It may receive some contributions to its volume through them, but in reality it is an independent ice body, nourished chiefly by direct snow precipitation from the clouds. And this is true, in large measure, of all the ice fields lying under the ice cascades. The Nisqually Glacier, accordingly, is not to be regarded as composed merely of the cascading névés, reunited and cemented together, but as taking a fresh start at these lower levels. Improbable though this may seem at first, it is nevertheless a fact that is readily explained.

The winter snows on Mount Rainier are heaviest in the vicinity of its base; indeed, the snowfall at those low levels is several times greater than that on the summit. This in itself may seem anomalous. So accustomed is one to think that the snowfall on high mountains increases with the altitude that it seems strange to find a case in which the opposite is true. Yet Mount Rainier stands by no means alone in this regard. The Sierra Nevada and the Andes, the Himalayas and the Alps, all show closely analogous conditions.

In each of these lofty mountain regions the precipitation is known to be heaviest at moderate altitudes, while higher up it decreases markedly. The reason is that the storm clouds--the clouds that carry most of the rain and snow--hang in a zone of only moderate elevation, while higher up the atmosphere contains but little moisture and seldom forms clouds of any great density.

In the Rainier region the height of the storm clouds is in large measure regulated by the relief of the Cascade Range; for it is really this cooling mountain barrier that compels the moisture-laden winds from the Pacific Ocean to condense and to discharge. It follows that the storm clouds are seldom much elevated above the sky line of the Cascade Mountains; they cling, so to speak, to its crest and ridges, while the cone of Mount Rainier towers high above them into serener skies. Many a day may one look down from the summit, or even from a halfway point, such as Camp Muir (10,062 feet), upon the upper surface of the clouds. Like a layer of fleecy cotton they appear, smothering the lower mountains and enveloping the volcano's base.

Clouds, it is true, are frequently seen gathering about the mountain's crown, usually in the form of a circular cap or hood, precursor of a general storm, but such clouds yield but very little snow.

No accurate measurements have been made of the snowfall at the mountain's foot, but in the Nisqually Valley, at Longmire Springs, the winter snows are known often to exceed 20 feet in depth. The summer heat at this low level (2,762 feet) is, of course, abundantly able to remove all of it, at least by the end of May. But higher up every thousand feet of elevation suffices to prolong appreciably the life of the snowy cover. In Paradise Park, for instance, at altitudes between 5,000 and 6,000 feet, huge snowdrifts encumber the flowering meadows until far into July. Above an altitude of 6,000 feet permanent drifts and snow fields survive in certain favored spots, while at the 7,000-foot level the snow line, properly speaking, is reached. Above this line considerable snow remains regularly from one winter to the next, and extensive ice fields and glaciers exist even without protection from the sun.