A stream of thick, viscous lava flowed slowly out of an opening at the southern base of Cinder Cone. As the lava crept down the gentle slopes of the valley, it crusted over, forming a black, slag-like surface. The surface was from time to time broken up and mixed with the softer portions beneath, so that the movement of the flow was still further retarded. At the lower end of the valley the lava occupied a portion of a body of water now known as Lake Bidwell; its rugged front made a dam across the valley above, forming Snag Lake. The stumps of the trees which were killed by the water when the lake was first formed are still standing.

One's feet sink deep into volcanic sands, and walking is tiresome. The lava field resulting from the last eruption is free from sand, but its rough surface, formed of broken blocks, is difficult to cross.

A few charred stumps rise out of the sand, pathetic remnants of the forest trees that were growing at the time of the first eruption. Most of the trees have completely disappeared, leaving shallow pits where they once stood.

It is exceedingly difficult to climb the cone, which rises over six hundred feet, for the slopes, composed of loose lapilli, are so steep that one slips back at every step nearly as far as he advances. From the summit a remarkable sight meets the eye. Within the rim of the main crater is a second crater with a rim nearly as high as the first, while the cavity within has a depth of about two hundred and fifty feet.

Because of the loose character of the material of which it is built, no streamlets have yet worn channels down the slopes of Cinder Cone, and except for the presence of two small bushes which cling to its side, it is just as bare and perfect in form as when first completed.

Little by little the forests are encroaching upon the sand-covered slopes about the cone, and in time these slopes, the black fields of lava, and the cone itself, will be covered with forests like the older lava fields and cinder cones which appear upon every hand.

THE MUD VOLCANOES OF THE COLORADO DESERT

The Colorado Desert is a strange, weird region. Here is a vast basin at the head of the Gulf of California which was once a part of the gulf, but is now separated from it by the delta of the Colorado River. With the drying up of the water, the centre of the basin was left a salt marsh more than two hundred and fifty feet below the level of the ocean. In summer the air quivers under the blazing sun, and it seems as if no form of life could withstand the scorching heat, but in winter the atmosphere is cool and full of life-giving energy.

Around this desert rise the mountains, some old and nearly worn down, their tops barely rising out of the long slopes of sand and gravel; others rugged and steep, lifting their crests far above the burning desert into the cold, clear sky.

Curious forms of plants and animals find their homes upon the slopes about the basin, where they adapt themselves to the heat and dryness. But toward the centre the soil is bare clay, for when the water dried up so much alkali and salt were left that nothing could grow.

However we do not now intend to study the plants or the animals, interesting though they are, but rather a group of mud volcanoes, which forms almost the only relief in the monotony of the bare plain. These volcanoes are in no way related to real volcanoes except in shape, for water and mud, instead of fire and lava, have been concerned in their building.

Once it required a long journey in wagons or upon horseback to reach the mud volcanoes, but now the railroad takes us within three miles of the spot. We alight from the train before a section house which stands in the midst of the great desert. Far, far away stretches the barren clay floor of the ancient lake. Here and there are scattered stunted shrubs, the only specimens of plant life which have been able to withstand the alkali in the clay.

Seen from the station, the volcanoes appear like dark specks almost upon the horizon, but in reality they are not far away, and an hour's brisk walk will bring us to them. The mud springs, which are scattered over an area of several hundred acres, present many strange and interesting features. There are holes in the earth with bubbling mud at the bottom, cones from the tops of which streams of muddy water issue, and ponds of mud, in some cases as thick as molasses, in others thin and watery. There are little jets of steam, strange odors, and a vista of many mingled colors. Taken altogether, it is a place quite different from any other that we have ever seen.

The ground is soft and marshy, and in some places undermined by the water, so that we have to take great care in walking about. Some of the smaller springs occupy round depressions, sometimes three or four feet across, which look as if they had been made by pressing a large pan down into the clay. The bubbling mud in the bottom of the pan, as well as the hot water in many of the springs, makes it easy to imagine that we are standing upon the top of a great cooking stove in which a hot fire is burning. As the gas with which the water is impregnated comes up through the mud, it forms huge bubbles which finally break and settle down, only to rise again. In this way concentric mud rings, perfect in form, are made to cover the entire surface of the pool.

Where there is little water, the surface of the mud hardens and leaves a small opening, through which the bubbling gas throws small columns of mud at regular intervals. From the large pools, some of which are forty to fifty feet in diameter, there comes a low murmuring sound like the boiling of many kettles. The water is sputtering and bubbling, and in some places it is hot enough to give off thin clouds of steam. Occasionally we get whiffs of sulphur, while about the borders of some of the ponds pretty crystals of this mineral can be found.

More commonly the pools are crusted about with a white deposit of salt, for they all contain more or less of this substance in solution. Around a few of the pools the mud is stained with the red tinge of iron, and red lines mark the paths of the streams as they run off from the pools toward the still lower portions of the desert.

The built-up cones or volcanoes appear in every stage, from the little ones a few inches high to the patriarchs, which in some cases have reached a height of twelve feet. These cones are formed by the hardening and piling up of mud about the openings; but when they have reached the height mentioned, the passages up through their centres, corresponding in each case to the throat of a real volcano, become clogged and new holes are formed in the mud at the base.

Many of these mud volcanoes closely resemble true volcanoes in form and structure. The mud which pours out at the top forms streams down the slopes very like those of molten lava. New cones are built upon the sides or at the bases of the old ones in much the same way as are those in the volcanic regions.

There are no signs of volcanic action in the vicinity of these mud springs, and it is likely that the water is forced to the surface by large quantities of gas produced by chemical changes taking place deep within the clay beds of the old lake. Similar springs occur farther south, nearer the mouth of the Colorado River, in the Yellowstone Park, and near Lassen Peak, but nowhere in America except in the Colorado desert have they formed such large and interesting mounds.

THE HISTORY OF A COAST LINE

The story of our Pacific coast reads more like a tale from the "Arabian Nights" than like a plain statement of events which have actually happened.

The meeting place of the land and ocean is not really so permanent a line as it appears. The shore has been continually moving back and forth throughout the long history of the earth. That which was dry land at one time was at another time deeply buried beneath the ocean. The Pacific border seems never to have been at rest. It has risen and sunk again repeatedly. It has been squeezed, folded, and broken, shaken by earthquakes, and disturbed by volcanic eruptions.

One might be led to think from this statement that it would not be safe to live on the Pacific coast, and that both animals and men would shun the region. The fact is, however, that these changes usually come to pass so very slowly that we are not aware of them. Severe earthquakes and volcanic disturbances take place so rarely in comparison with the length of a man's life, that we may pass our whole lives without experiencing any of these violent disturbances. The Pacific coast region, with its forest-covered mountains, fertile valleys, and beautiful homes, presents so quiet and peaceful an appearance that it is difficult to believe that parts of its history have been so tumultuous.

Perhaps you will ask how we can know so much about the past. It is true that no one was here to witness the events which are supposed to have taken place. But Nature has left a record of her doings which we have only to see and understand in order to learn with certainty many things which happened in the far distant past.

Too many of us go through life seeing and understanding almost as little of the world about us as if we were blind. Our early ancestors were obliged to understand many things about Nature and to cultivate clear and close observation for the sake of self-preservation. The very life of the savage depends upon the training of his eyes. He must be able to tell the meaning of a distant object or an indistinct trail, for his enemies may have passed that way recently. If we could bring the sharp eyes of the savage to our aid, the world would mean much more to us.

In order to learn something of the history of the Pacific shore line, we must see what the waves are doing at the present time. The projecting points of land are being worn away (Fig. 33). The waves form the cliffs against which they beat, and sometimes, as they eat their way slowly into the land, they cut off portions and leave them standing alone as islands.

The pebbles and boulders (Fig. 34) were once angular fragments torn from the cliff. They have been washed about and hurled against the solid rock until they have been worn smooth; and the cliff in turn has had a cave ground out at its base. Above the lower cave there is a remnant of a second one, with pebbles upon its floor. This was made when the land stood ten feet lower than at present.

As the waves wear away the loose earth and the solid rock below it, moving the cliffs inland, they leave a comparatively smooth surface which is partly exposed at low tide. The fact that this surface is not marked by stream channels, as is the land, helps us to realize the great difference between the irregular surface of the latter and the plain-like character of the ocean floor.

Along the whole coast of California there are many old sea beaches and cliffs which the waves abandoned long ago. The highest of these beaches lies so far up the slopes of the mountains bordering the ocean that it makes us wonder what the geography of California could have been like when the region was so deeply submerged.

The lowest and newest terrace is the one shown in Fig. 35, ten feet above the ocean. Each succeeding terrace is less distinct, and the highest, fourteen hundred feet in elevation, can now be distinguished in only a few places. Where the old sea cliffs are best preserved they form a series of broad, flat steps, rising one above the other. Each bench, or terrace as it is commonly called, is a part of an old plain cut out of the land by the waves when the ocean stood at that level. The steeper slope rising at the back is the remnant of the cliff against which the waves used to beat. If we are fortunate, we shall find at its base some water-worn pebbles and possibly a few fragments of sea-shells. The crumbling of the rocks and the erosive action of the rills are fast destroying the old cliffs, so that in many places they have entirely disappeared.

Upon the seaward face of San Pedro Hill, in southern California, there are eleven terraces, rising to a height of twelve hundred feet. What an interesting record this shows! Long ago the land stood twelve hundred feet lower than at present, and the waves beat about San Pedro Hill, nearly submerging it. Then the land began to rise, but stopped after a time, and the waves cut a terrace. The upward movement was continued, with repeated intervals of rest, until the land stood higher than it does now.

North of San Francisco there stands a terrace fourteen hundred feet above the ocean. Numerous terraces appear along the Oregon coast, but those in Washington are not as high as those in California. It is probable that the land in this region was not so deeply submerged.

The ancient shore lines of British Columbia and Alaska are now deeply buried beneath the ocean, as those of California once were. The fiords, so common in these countries, are old river valleys which have been drowned by the sinking of the land. The islands were once portions of the coast mountains, but have been cut off by the same process.

Let us picture in our minds the changes in the geography of the Pacific coast of the United States which must have been made by a sinking of the land to a depth of only six hundred feet. We will begin upon the north, at the Strait of Fuca.

Puget Sound once opened to the south as well as to the north, so that the Olympic Mountains formed an island. The broad and fertile Willamette Valley was but an arm of the sea, somewhat like Puget Sound to-day. The body of water which once filled this valley has been called Willamette Sound. The ocean overspread the low Oregon coast, and reached far up the valleys of the Umpqua and Rogue rivers. But the boundaries of the Klamath Mountains were not greatly changed, for in many places they rise quite abruptly from the present shore line.

All the large valleys of California were flooded, including the San Joaquin-Sacramento valley, which was then a great sound, open to the ocean in the region of the present Strait of Carquinez. The Coast range was broken up into islands and peninsulas. The islands off the coast of southern California are high and therefore were not entirely submerged. The Gulf of California spread over the Colorado Desert, while from the west the water penetrated inland over the plain of Los Angeles to a point beyond San Bernardino, so that at the San Gorgonio pass only a narrow neck of land connected the San Jacinto Mountains and the Peninsula Range with the mainland.

If California had been inhabited at this time, the state would not have been noted for orchards and grain-fields, but rather for its mineral wealth. There would have been comparatively little low land fit for cultivation, but the mountains, where almost all the precious metals are found, would have appeared nearly as they do to-day.

The surface of the earth may be divided into the ocean basins and the continental masses which rise above them, but we must not make the mistake of thinking that the shore line always corresponds with the border of the continental masses. We have learned that the land is almost always moving slowly up or down, so that the shore is continually changing back and forth. At one time the shore line may be far within the borders of the continent, as we have seen was once the case upon our Pacific coast; at another time, if the land should rise, the shore line might coincide with the real border of the continent. By the real border of the continent we mean the line along which the earth slopes down steeply to the abysmal depths of the ocean.

It is an interesting fact that outside the present shore line of California there is a submerged strip of the continent varying from ten to one hundred and fifty miles in width. This strip of land is like a bench upon the side of the continent, and is known as the continental plateau. The water over the plateau is comparatively shallow. Upon one side the land rises, while upon the other there is a rapid descent into the deep Pacific. The surface of the plateau is in general fairly smooth, but in places mountains lift their summits above the water and form islands.

There was a time, thousands of years earlier than the period when California was so nearly covered by the waters of the Pacific, when this land stood far higher than it does now. The coast line was then much farther west, near the border of the submarine plateau. The Santa Barbara Islands at that time formed a mountain range upon the edge of the continental land. This fact was established by the discovery upon one of the islands of a large number of bones of an extinct American elephant. These animals could have reached the submerged mountains only at a time when there was dry land between them and the present shore line. We should like to know how it came about that these bones were left where they are. Perhaps the land sank so suddenly that the water cut the elephants off from the mainland and compelled them to spend the remainder of their lives upon these islands.

While the land stood so high, some of the larger streams wore deep channels across what is now the submarine plateau. These channels have been discovered by soundings made from the ships of the United States Coast Survey. The largest of the submerged valleys extends through the Bay of Monterey, and runs so close to the shore that it has offered a favorable location for a wharf.

Before the buried valleys upon the northern coast of California were all known, the presence of one of them led to the wreck of a ship. The shore was obscured by fog, but the soundings made by the sailors showed deep water and led them to believe they were a long distance from land, when suddenly the ship drifted in upon the rocks.

The last significant movement of the land of the Pacific border was a downward one. It flooded the mouths of the streams and formed all the large harbors which are of so great commercial importance.

San Francisco Bay occupies a great stretch of lowland at the meeting of several valleys of the Coast Ranges and forms the outlet for the most important drainage system of California. If this region had been settled before the subsidence of the land which let in the ocean through the Golden Gate, how the farmers would have lamented the flooding of their fertile lands! But we can understand how small the loss would have been, compared with the advantages to be gained from the magnificent harbor which now exists here. If the land had not sunk the history of the Pacific coast would have been far different.

Puget Sound, another very important arm of the ocean, is also a submerged valley, but it has had an entirely different history from that of San Francisco Bay. The valley was at one time occupied by a great glacier which came down from the Cascade Range and moved northwest through the sound and into the Strait of Juan de Fuca, scouring and polishing the rocks over which it passed. A little island near Anacortes (Fig. 36) has been rounded by the action of the ice into a form like a whale's back.

The sinking of the land flooded the lower Columbia River and the mouth of the Willamette, so that ocean ships may now go up as far as Portland. The currents and waves soon threw up bars across the mouths of the smaller streams, and formed lagoons behind them. Ships frequently have difficulty in entering many of the harbors because of the sand bars which have been built up part way to the surface of the water.

It is thought that along some portions of the coast there has recently been a slight upward movement of the land. Figure 37 shows a bit of California coast, near San Juan, where the Santa Fé railroad has laid its tracks for several miles along a strip of abandoned beach, at the base of a cliff against which the waves once beat.

At the northern end of Vancouver island there is a deep arm of the ocean called Quatsino Sound. A limestone cliff upon the shore of this sound (Fig. 38) has been undermined by the dissolving of the limestone, but now the water lacks three feet of rising to the notch which it recently formed.

THE DISCOVERY OF THE COLUMBIA RIVER

The influence exerted by the various features of the land and water upon the settlement of a new region are not always fully appreciated. If the entrance to San Francisco Bay had been broader and more easily discerned by the early navigators who sailed past it, and if the mouth of the Columbia River had not been obscured by lowlands and a line of breakers upon the bar, the history of western America would probably have been very different.

In the seventeenth century the prospect seemed to be that Spain would control the Pacific Ocean. She claimed, by right of discovery, all the lands bordering upon this ocean and the exclusive right to navigate its waters. Every vessel found there without license from the court of Spain was, by royal decree, to be confiscated.

It is interesting, after all these years and with our present knowledge, to look back and see how unreasonable were the claims of Spain. In the fifteenth century the extent of the Pacific ocean was not known. In fact, men's ideas as to the distribution of land and water over the earth were so indefinite that it was at first supposed that the islands which Columbus discovered belonged to the East Indies.

The claims of Spain to the Pacific Ocean were based upon its discovery by Balboa, but she never made any serious efforts to enforce them, for the attempt would have involved her in war with all the maritime nations of Europe. Spain lacked the ability to take advantage of the great discoveries which her navigators and explorers had made, and for that reason she merely looked on, though with jealous eyes, when in the eighteenth century the ships of England, France, Holland, and Russia entered the Pacific Ocean with a view to exploration and conquest.

Determined at last to support their claim to the Pacific coast of North America, the Spaniards began to realize the necessity of exploring it more fully and of founding settlements. It was their plan to take possession of the whole region between Mexico upon the south and the Russian trading posts along the shores of Alaska. As exploration by land was impossible because of mountain ranges and deserts, the Spanish adventurers were forced to rely upon the ocean, with all its uncertainties of storm and contrary winds.

Between 1774 and 1779 voyages were made as far north as Queen Charlotte's Island, in latitude 54°. A station was established and held for many years at Nootka Sound, upon the west coast of Vancouver Island. The first expedition passed the Strait of Juan de Fuca apparently without seeing it, although there was a rumor to the effect that a broad opening into the land had been discovered by a certain Juan de Fuca in 1592, while he was exploring in the employ of Spain. The latitude of this opening, as he gave it, nearly corresponds to that of the strait which now bears his name.

For many years the attempt to discover a passage around the northern part of America engaged the early navigators upon both the Atlantic and Pacific oceans. Their desire to find an easy route to India spurred them to constant effort. For a time it was believed that such an opening actually existed, and mariners went so far as to give it a name, calling it the Straits of Anian. The reputed discoveries of Juan de Fuca materially strengthened the general belief in a passage to the northward of America.

Vizcaino, in his voyage of 1603, reached latitude 43° north and thought that he had discovered a great river flowing into the Pacific Ocean. This opening, although south of the point supposed to have been reached by Juan de Fuca, was believed for a time to be the entrance to the long-sought Straits of Anian. During the latter part of the seventeenth century California was represented upon the Spanish maps as an island having Cape Blanco, which Vizcaino discovered and named, as its northern point, and separated from the mainland by an extension of the Gulf of California northward.

To return now to the Spanish explorations, in the latter part of the seventeenth century we find that Heceta, following the first expedition, succeeded in getting as far as Vancouver Island, where, having been parted from an accompanying ship by a storm, he turned southward, passing the Strait of Juan de Fuca and keeping close by the shore. In latitude 46° 17' he found an opening in the coast from which a strong current issued. He felt sure that he had discovered the mouth of some large river. Upon the later Spanish maps this was called Heceta's Inlet, or River of San Roque. A glance at the map will show how closely the latitude given corresponds to the mouth of the river which was discovered later by Captain Gray and named, after his ship, the Columbia.

A short time before Heceta's discovery, Captain Jonathan Carver of Connecticut set out on an exploring tour, partly for the purpose of determining the width of the continent and the nature of the Indian inhabitants. He mentions four great rivers rising within a few leagues of one another, "The river Bourbon (Red River of the North) which empties itself into Hudson's Bay, the waters of the St. Lawrence, the Mississippi, and the river Oregon, or River of the West, that falls into the Pacific Ocean at the Straits of Anian." Carver's descriptions are fanciful, and it is not likely that he ever saw the river which is now known as the Columbia, although there is a possibility that he heard stories from the Indians of a great river upon the western slope of the Rocky Mountains, and invented for it the name Oregon.

In 1787 Meares, an English trader, visited the coast, and sailing southward from the Strait of Juan de Fuca, attempted to find the river San Roque as it was laid down upon the Spanish charts. Reaching the proper latitude, Meares rounded a promontory and found behind it a bay which he was unable to enter because of a continuous line of breakers extending across it. He became satisfied that there was no such river as the San Roque, and named the promontory Cape Disappointment and the bay Deception Bay. If Meares had entered the bay through the breakers, the English would undoubtedly have made good their claim to the discovery of the Columbia River.

After the Revolution, American trading ships began to extend their operations into the North Pacific. In 1787 two such vessels left Boston, one of them under command of a Captain Gray. After reaching the Pacific, the ships were parted during a storm, and Captain Gray finally touched the American coast near the forty-sixth degree of north latitude. For nine days he tried to enter an opening which was in all probability the one attempted by Meares. After nearly losing his ship and suffering an Indian attack, he sailed north to Nootka Sound.

Captain Gray returned to Boston, but in 1790 started upon another trading expedition in command of the ship Columbia. Arriving safely in the North Pacific, he spent the winter of 1791-1792 upon Vancouver Island.

Vancouver, whose name has been given to the largest island upon the western coast of North America, and who did so much to make known the intricate coast line of the Puget Sound region, arrived upon the scene in 1792. He was authorized to carry on explorations, and to treat with Spain concerning the abandonment of the Spanish claim to Nootka Sound.

Vancouver sailed up the coast, keeping a close lookout for the river San Roque. No opening in the land appeared, although at one spot he sailed through a muddy-colored sea which he judged was affected by the water of some river. Upon reaching the Strait of Fuca, Vancouver expressed the opinion that there was no river between the fortieth and forty-eighth degrees of north latitude, "only brooks insufficient for our vessels to navigate."

Shortly after this time, Vancouver met Captain Gray with his ship Columbia. The disheartened explorer placed no confidence in Captain Gray's report that, upon his former voyage, he had discovered a large river to the south. Vancouver in his narrative says, "I was thoroughly convinced that we could not possibly have passed any safe navigable opening, harbor, or place of security for shipping on this coast from Cape Mendocino to the promontory of Closset" (Cape Flattery).

Captain Gray, however, determined to make further investigations. He sailed southward and entered a port now known as Gray's Harbor, where he spent several days trading with the Indians. From this harbor he ran on south for a few miles past Cape Disappointment, and then sailed through an opening in the breakers into a bay which he supposed formed the mouth of the river of which he was in search. He finally anchored, as he says, "in a large river of fresh water."

Later Captain Gray took the vessel twelve or fifteen miles up the river, and would have gone farther if he had not wandered into the wrong channel. When he left the river he named it the Columbia in honor of his vessel. Thus by the right of actual discovery the United States was at last able to make good its claim to the river.

The English claimed that Gray did not enter the river itself, as the tide sets up many miles farther than the point which his ship reached. They insisted that what he saw was simply a bay. But the truth is that Gray was actually in the mouth of the river. The mere fact that the tide enters the lower portion of the river makes no difference. The actual mouth of the Columbia is marked by the north and south coast line. The entrance of the tide water, and the backing of the current for many miles up stream, is the result of a recent sinking of the land. The same features are presented by the Hudson River.

If the English had discovered and entered the river first it is probable that this stream would have become the boundary line between the United States and British Columbia, in which case the whole northern portion of the Oregon territory would have been lost to us. As it was, the English laid insistent claim to the northern bank of the river and established trading posts at various points. The lowest of these posts stood upon the site of Fort Vancouver, a little above the mouth of the Willamette River.

The famous exploring expedition under Captains Lewis and Clark wintered at the mouth of the Columbia in 1804-1805, in a group of rude log cabins known as Fort Clatsop. The first settlement in the vicinity was made in 1811, when a fur company organized by John Jacob Astor attempted to establish a trading post upon the Columbia. Two parties were sent out from New York. One travelled by water around Cape Horn, while the other, with great difficulty, crossed the continent by the way of the Missouri, Snake, and Columbia rivers. The undertaking proved unsuccessful, for after the War of 1812 began supplies could no longer be sent safely to the post.

The Astor company finally surrendered its establishment to an English company, and in this way the control of the river was transferred to England. With the return of peace the post was restored to the United States, and its location is marked now by the city of Astoria.

What small things sometimes determine the trend of great events! A little more care and energy on the part of Vancouver or Meares would have placed the Columbia River in the hands of the English. The existence of an open river mouth without any breaking bar would have brought about the same result.

The Spaniards came first to the Pacific slope, claiming the whole coast as far north as the Russian possessions. Later the United States, by treaty with Spain and Russia, acquired a right to all that portion of the Pacific coast of North America which lies between California and the Russian possessions. But because of the greater energy of the English, and the failure upon the part of the United States to realize the value of this vast region, a considerable section was again lost by the terms of the treaty which made the forty-ninth parallel the boundary line. The intelligence and energy of Captain Gray alone preserved to us the rich lands of Washington.

THE GREAT BASIN AND ITS PECULIAR LAKES

As our country was slowly being explored and settled, one region was brought to light which Nature seemed to have left unfinished and in a desolate condition. This barren stretch of country was once marked upon the maps as the Great American Desert, and included a large part of the extensive region lying between the Rocky Mountains upon the east and the Sierra Nevada Mountains upon the west. To the south lay the Grand Cañon of the Colorado, while upon the north the boundary was formed by the cañons of the Snake and Columbia rivers.

After a time it was found that this region, covering about two hundred and twenty-five thousand square miles, not only was extremely dry, but had no outlet to the ocean. A rim of higher land all about made of it so perfect a basin that it became known as the Great Basin. None of the water that falls upon the surface of this basin ever reaches the ocean through surface streams. Some of it soaks into the rocks, but the greater part is evaporated into the dry air.

We have already learned something about the way in which the ridges and hollows of the earth's surface are made. We have learned of the wrinkling of the crust, of the formation of fissures, and of the erosive work of running water. The interesting features of the Great Basin are mainly the result of two causes: the sinking of a portion of the earth's surface, and the lack of rainfall.

Long ago the Wasatch Range of eastern Utah and the Sierra Nevadas of California formed parts of a vast elevated plateau. Then there came a time when the forces holding up the plateau were relaxed, and as the weight of the plateau pressed it down, the solid rocks broke into huge fragments. Some of the blocks thus made sank and formed valleys; others were tilted or pushed up and formed mountains. Thus the north and south mountain ranges and valleys of the Great Basin were born.

We must understand, then, that the Great Basin is not a simple depression with higher land all about. The breaking up of the surface produced many basins, large and small. Some of these basins are six thousand feet above the level of the sea, others are much lower, and one has been dropped below the level of the sea, so that if it were not for barriers the water would flow in. Some of the basins are rimmed all about by steep mountains, others are so broad and flat that it is difficult to tell that they really are basins. Many of the valleys are so connected with one another that if a heavy rainfall should ever occur drainage systems would be quickly established.

The Great Basin now appears like the skeleton of a dried-up world; but if the climate should change and become like that of the Mississippi Valley, the surface of the desert would undergo a wondrous transformation. The hundreds of basins, if fed by streams from the surrounding mountains, would then become lakes. The highest, overflowing, would empty into a lower, and this in turn into a still lower basin, until the water had accumulated in vast inland seas. These seas, overflowing the rim of the Great Basin at its lowest points, would send rivers hastening away to the ocean.

What a region of lakes this would be for a time! Then they would begin to disappear, for lakes are short-lived as compared with mountains. Some would be filled with clay and gravel brought by the streams. Others would be drained by a cutting down of their outlets.

Great Salt Lake, which is the only body of water in the Basin that has ever sent a stream to the ocean, was lowered four hundred feet by the washing away of the rock and earth at its outlet.

We know that the rainfall never has been heavy in this region since the Great Basin was formed, although at one time it was sufficiently great to form two inland seas, one in northwestern Nevada, the other in Utah.

The chief reason for the dryness of the Great Basin is the presence of that lofty barrier, the Sierra Nevada mountain range, between the Basin and the Pacific Ocean. The storms, which usually come from the ocean, are intercepted by this range, and the greater portion of their moisture is taken away. The little moisture that remains falls upon the highlands of the Great Basin, and so relieves its surface from utter barrenness. The adjacent slopes of the Sierra Nevada and Wasatch ranges furnish numerous perennial streams which feed the lakes about the borders of the Basin, such as Great Salt Lake, Pyramid, Walker, Mono, Honey, and Owens lakes. The wet weather streams, flowing down the desert mountains for a short time each year, frequently form broad, shallow lakes which disappear with the coming of the summer sun.

The climate of the Great Basin has changed from time to time. During one period it was much drier than it is now, and the lakes were nearly or quite dried up. It must have been a desolate region then, shunned by animals and forbidden to man.

During the Glacial period, a few thousand years ago, the climate was moister and cooler than it is now. The mountains were covered with deep snows, and glaciers crept down the slopes of the higher peaks. Great Salt Lake covered all northwestern Utah; to this former body of water the name Bonneville has been given, in honor of a noted trapper. Pyramid, Winnemucca, Carson, Walker, and Honey lakes, now separated from one another by sagebrush deserts, were then united in one great lake, to which the name Lahontan has been given, in honor of an early French explorer.

Lake Lahontan covered a large portion of northwestern Nevada and penetrated into California. It was broken into long winding arms and bays by various mountain ranges. The deepest portion of this ancient lake is now occupied by Pyramid Lake, which is, perhaps, the most picturesque of all the Basin lakes. Fish can live in the waters of this lake, although nearly all the others are so salty or so alkaline that they support none of the ordinary forms of life.

Upon the Black Rock Desert, in northern Nevada, there are large springs once covered by Lake Lahontan, in which fish are found. It is thought that the ancestors of these fish must have been left there at the time of the drying up of the water.

After the Glacial period the present arid climate began to prevail in the land. Hundreds of the shallow lakes which had been scattered over this extensive region disappeared. Others contained water for only a portion of each year. A body of water which is not permanent, but comes and goes with the seasons, we call a playa lake. Many of these playa lakes present in summer a hard, yellow-clay floor of many miles in extent and entirely free from vegetation. The beds of others are covered with a whitish crust, formed of the various salts which were in solution in the lake water.

An important feature of the lakes of the Great Basin is the presence of large quantities of such substances as common salt, soda, borax, and nitre. The ocean is salt because it has no outlet, while the rivers of the globe are continually bringing into it various minerals, dissolved from the rocks over which they flow. Lakes with outlets are not salty, because with a continuous change of the water there is no opportunity for the minerals to accumulate, although they are always present in small quantities. Any lake which does not receive enough running water to cause it to overflow the borders of its basin, will in course of time become rich in various kinds of salt.

No two of the lakes of the Great Basin are alike in the composition of their waters. This fact may be due to a difference in the rocks about the lake basin, to the presence of varying mineral springs, or to the drying up of one or more of the lakes at some time so that their former salts were buried under sands and clays when the water again filled the basin.

Great Salt Lake contains little besides common salt. In Mono Lake, soda and salt are equally important constituents, while Owens Lake contains an excess of soda. In other basins borax was present in such quantities that when the waters dried up it formed important deposits. The value of these deposits is now fully understood, and many enterprising companies are at work separating and purifying the borax.

Owens Lake was once fresh, although now it is so strong with soda that it would destroy the skin if a bather should remain in it very long. The former outlet of this lake was toward the south, through a pass separating the Sierra Nevada from the Coso Mountains. For a distance of thirty miles the old river-bed has been transformed into a wagon road, and it is interesting to ride all day along the bed of this dead river, past bold cliffs against which the waters once surged and foamed. The river emptied far to the south, into a broad, shallow lake whose former bed is now white with soda and borax. The old beach lines stand out distinctly upon the slopes of the enclosing mountains.

The lake bed is now the seat of an important industry—the gathering of the borax and its refining. There are extensive buildings at one spot upon its border, and men come and go across the blinding white surface. A twenty-mule team dragging three huge wagons creeps slowly along the base of the distant mountains, but all that can be distinguished is a cloud of dust.