Carib natives who lived at Morne Rond fled from their houses to Kingstown. As the third day drew to a close flames sprang pyramidically from the crater, accompanied by loud thunder and electric flashes, which rent the column of smoke hanging over the volcano. Eruptive matter pouring from the northwest side plunged over the cliff, carrying down rocks and woods in its course. The island was shaken by an earthquake and bombarded with showers of cinders and stones, which set houses on fire and killed many of the natives.

THE TERRIBLE EARTHQUAKE AT CARACAS

For nearly two years before this explosion earthquakes had been common, and sea and land had been agitated from the valley of the Mississippi to the coasts of Venezuela and the mountains of New Grenada, and from the Azores to the West Indies. On March 26, 1812, these culminated in the terrible tragedy, spoken of above, of which Humboldt gives us a vivid account.

On that day the people of the Venezuelan city of Caracas were assembled in the churches, beneath a still and blazing sky, when the earth suddenly heaved and shook, like a great monster waking from slumber, and in a single minute 10,000 people were buried beneath the walls of churches and houses, which tumbled in hideous ruin upon their heads. The same earthquake made itself felt along the whole line of the Northern Cordilleras, working terrible destruction, and shook the earth as far as Santa Fe de Bogota and Honda, 180 leagues from Caracas. This was a preliminary symptom of the internal disorder of the earth.

While the wretched inhabitants of Caracas who had escaped the earthquake were dying of fever and starvation, and seeking among villages and farms places of safety from the renewed earthquake shocks, the almost forgotten volcano of St. Vincent was muttering in suppressed wrath. For twelve months it had given warning, by frequent shocks of the earth, that it was making ready to play its part in the great subterranean battle. On the 27th of April its deep-hidden powers broke their bonds, and the conflict between rock and fire began.

THE MOUNTAIN STONES A HERD-BOY

The first intimation of the outbreak was rather amusing than alarming. A negro boy was herding cattle on the mountain side. A stone fell near him. Another followed. He fancied that some other boys were pelting him from the cliff above, and began throwing stones upward at his fancied concealed tormentors. But the stones fell thicker, among them some too large to be thrown by any human hand. Only then did the little fellow awake to the fact that it was not a boy like himself, but the mighty mountain, that was flinging these stones at him. He looked up and saw that the black column which was rising from the crater's mouth was no longer harmless vapor, but dust, ashes and stones. Leaving the cattle to their fate, he fled for his life, while the mighty cannon of the Titans roared behind him as he ran. For three days and nights this continued; then, on the 30th, a stream of lava poured over the crater's rim and rushed downward, reaching the sea in four hours, and the great eruption was at an end.

On the same day, says Humboldt, at a distance of more than 200 leagues, "the inhabitants not only of Caracas, but of Calabozo, situated in the midst of the Lianos, over a space of 4,000 square leagues, were terrified by a subterranean noise which resembled frequent discharges of the heaviest cannon. It was accompanied by no shock, and, what is very remarkable, was as loud on the coast as at eighty leagues' distance inland, and at Caracas, as well as at Calabozo, preparations were made to put the place in defence against an enemy who seemed to be advancing with heavy artillery."

It was no enemy that man could deal with. Fortunately, it confined its assault to deep noises, and desisted from earthquake shocks. Similar noises were heard in Martinique and Guadeloupe, and here also without shocks. The internal thunder was the signal of what was taking place on St. Vincent. With this last warning sound the trouble, which had lasted so long, was at an end. The earthquakes which for two years had shaken a sheet of the earth's surface larger than half Europe, were stilled by the eruption of St. Vincent's volcanic peak.

BARBADOS COVERED WITH ASHES

Northeast of the original crater of the Soufriere a new one was formed which was a half mile in diameter and five hundred feet deep. The old crater was in time transformed into a beautiful blue lake, as above stated, walled in by ragged cliffs to a height of eight hundred feet.

It was looked upon as a remarkable circumstance that although the air was perfectly calm during the eruption, Barbados, which is ninety-five miles to the windward, was covered inches deep with ashes. The inhabitants there and on other neighboring islands were terrified by the darkness, which continued for four hours and a half. Troops were called under arms, the supposition from the continued noise being that hostile fleets were in an engagement.

The movement of the ashes to windward, as just stated, was viewed as a remarkable phenomenon, and is cited by Elise Reclus, in "The Ocean," to show the force of different aerial currents; "On the first day of May, 1812, when the northeast trade-wind was in all its force, enormous quantities of ashes obscured the atmosphere above the Island of Barbados, and covered the ground with a thick layer. One would have supposed that they came from the volcanoes of the Azores, which were to the northeast; nevertheless they were cast up by the crater in St. Vincent, one hundred miles to the west. It is therefore certain that the debris had been hurled, by the force of the eruption, above the moving sheet of the trade-winds into an aerial river proceeding in a contrary direction." For this it must have been hurled miles high into the air, till caught by the current of the anti-trade winds.

KINGSLEY'S VISIT TO SAINT VINCENT

From Charles Kingsley's "At Last" we extract, from the account of the visit of the author to St. Vincent, some interesting matter concerning the 1812 eruption and its effect on the mountain; also its influence upon distant Barbados, as just stated.

"The strangest fact about this eruption was, that the mountain did not make use of its old crater. The original vent must have become so jammed and consolidated, in the few years between 1785 and 1812, that it could not be reopened, even by a steam force the vastness of which may be guessed at from the vastness of the area which it had shaken for two years. So, when the eruption was over, it was found that the old crater-lake, incredible as it may seem, remained undisturbed, so far as has been ascertained; but close to it, and separated only by a knife-edge of rock some 700 feet in height, and so narrow that, as I was assured by one who had seen it, it is dangerous to crawl along it, a second crater, nearly as large as the first, had been blasted out, the bottom of which, in like manner, was afterward filled with water.

"I regretted much that I could not visit it. Three points I longed to ascertain carefully—the relative heights of the water in the two craters; the height and nature of the spot where the lava stream issued; and, lastly, if possible, the actual causes of the locally famous Rabacca, or 'Dry River,' one of the largest streams in the island, which was swallowed up during the eruption, at a short distance from its source, leaving its bed an arid gully to this day. But it could not be, and I owe what little I know of the summit of the soufriere principally to a most intelligent and gentleman-like young Wesleyan minister, whose name has escaped me. He described vividly, as we stood together on the deck, looking up at the volcano, the awful beauty of the twin lakes, and of the clouds which, for months together, whirl in and out of the cups in fantastic shapes before the eddies of the trade wind.

BLACK SUNDAY AT BARBADOS

"The day after the explosion, 'Black Sunday,' gave a proof of, though no measure of, the enormous force which had been exerted. Eighty miles to windward lies Barbados. All Saturday a heavy cannonading had been heard to the eastward. The English and French fleets were surely engaged. The soldiers were called out; the batteries manned; but the cannonade died away, and all went to bed in wonder. On the 1st of May the clocks struck six, but the sun did not, as usual in the tropics, answer to the call. The darkness was still intense, and grew more intense as the morning wore on. A slow and silent rain of impalpable dust was falling over the whole island. The negroes rushed shrieking into the streets. Surely the last day was come. The white folk caught (and little blame to them) the panic, and some began to pray who had not prayed for years. The pious and the educated (and there were plenty of both in Barbados) were not proof against the infection. Old letters describe the scene in the churches that morning as hideous—prayers, sobs, and cries, in Stygian darkness, from trembling crowds. And still the darkness continued and the dust fell.

INCIDENTS AT BARBADOS

"I have a letter written by one long since dead, who had at least powers of description of no common order, telling how, when he tried to go out of his house upon the east coast, he could not find the trees on his own lawn save by feeling for their stems. He stood amazed not only in utter darkness, but in utter silence; for the trade-wind had fallen dead, the everlasting roar of the surf was gone, and the only noise was the crashing of branches, snapped by the weight of the clammy dust. He went in again, and waited. About one o'clock the veil began to lift; a lurid sunlight stared in from the horizon, but all was black overhead. Gradually the dust drifted away; the island saw the sun once more, and saw itself inches deep in black, and in this case fertilizing, dust. The trade-wind blew suddenly once more out of the clear east, and the surf roared again along the shore.

"Meanwhile a heavy earthquake-wave had struck part at least of the shores of Barbados. The gentleman on the east coast, going out, found traces of the sea, and boats and logs washed up some ten to twenty feet above high-tide mark; a convulsion which seemed to have gone unmarked during the general dismay.

"One man at least, an old friend of John Hunter, Sir Joseph Banks and others their compeers, was above the dismay, and the superstitious panic which accompanied it. Finding it still dark when he rose to dress, he opened (so the story used to run) his window; found it stick, and felt upon the sill a coat of soft powder. 'The volcano in St. Vincent has broken out at last,' said the wise man, 'and this is the dust of it.' So he quieted his household and his negroes, lighted his candles, and went to his scientific books, in that delight, mingled with an awe not the less deep, because it is rational and self-possessed, with which he, like the other men of science, looked at the wonders of this wondrous world."



CHAPTER XXX.

Submarine Volcanoes and their Work of Island Building.

In November, 1867, a volcano suddenly began to show signs of activity beneath the deep sea of the Pacific Ocean. There are some islands nearly two thousands miles to the east of Australia called the Navigator's Group, in which there had been no history of an eruption, nor had such an event been handed down by tradition. Most of the islands in the Pacific Ocean are old volcanoes, or are made up of rocks cast forth from extinct burning mountains. They rise up like peaks through the great depths of the ocean, and the top, which just appears above the sea-level, is generally encircled by a growth of coral. Hence they are termed coral islands. These islands every now and then rise higher than the sea-level, owing to some deep upheaving force, and then the coral is lifted up above the water, and become a solid rock. But occasionally the reverse of this takes place, and the islands begin to sink into the sea, owing to a force which causes the base of the submarine mountain to become depressed. Sometimes they disappear. All this shows that some great disturbing forces are in action at the bottom of the sea, and just within the earth's crust, and that they are of a volcanic nature.

For some time before the eruption in question, earthquakes shook the surrounding islands of the Navigator's Group, and caused great alarm, and when the trembling of the earth was very great, the sea began to be agitated near one of the islands, and vast circles of disturbed water were formed. Soon the water began to be forced upwards, and dead fish were seen floating about. After a while, steam rushed forth, and jets of mud and volcanic sand. Moreover, when the steam began to rush up out of the water, the violence of the general agitation of the land and of the surface of the sea increased.

AN ERUPTION DESCRIBED

When the eruption was at its height vast columns of mud and masses of stone rushed into the air to a height of 2,000 feet, and the fearful crash of masses of rock hurled upwards and coming in collision with others which were falling attested the great volume of ejected matter which accumulated in the bed of the ocean, although no trace of a volcano could be seen above the surface of the sea. Similar submarine volcanic action has been observed in the Atlantic Ocean, and crews of ships have reported that they have seen in different places sulphurous smoke, flame, jets of water, and steam, rising up from the sea, or they have observed the waters greatly discolored and in a state of violent agitation, as if boiling in large circles.

New shoals have also been encountered, or a reef of rocks just emerging above the surface, where previously there was always supposed to have been deep water. On some few occasions, the gradual building up of an island by submarine volcanoes has been observed, as that of Sabrina in 1181, off St. Michael's, in the Azores. The throwing up of ashes in this case, and the formation of a conical hill 300 feet high, with a crater out of which spouted lava and steam, took place very rapidly. But the waves had the best of it, and finally washed Sabrina into the depths of the ocean. Previous eruptions in the same part of the sea were recorded as having happened in 1691 and 1720.

In 1831, a submarine volcanic eruption occurred in the Mediterranean Sea, between Sicily and that part of the African coast where Carthage formerly stood. A few years before, Captain Smyth had sounded the spot in a survey of the sea ordered by Government, and he found the sea-bottom to be under 500 feet of water. On June 28, about a fortnight before the eruption was visible, Sir Pulteney Malcom, in passing over the spot in his ship, felt the shock of an earthquake as if he had struck on a sandbank, and the same shocks were felt on the west coast of Sicily, in a direction from south-west to north-east.

BUILDING UP OF AN ISLAND BY SUBMARINE VOLCANOES

About July 10, the captain of a Sicilian vessel reported that as he passed near the place he saw a column of water like a waterspout, sixty feet high, and 800 yards in circumference, rising from the sea, and soon after a dense rush of steam in its place, which ascended to the height of 1,800 feet. The same captain, on his return eighteen days after, found a small island twelve feet high, with a crater in its centre, throwing forth volcanic matter and immense columns of vapor, the sea around being covered with floating cinders and dead fish. The eruption continued with great violence to the end of the same month. By the end of the month the island grew to ninety feet in height, and measured three-quarters of a mile round. By August 4th it became 200 feet high and three miles in circumference; after which it began to diminish in size by the action of the waves. Towards the end of October the island was levelled nearly to the surface of the sea.

Naval officers and foreign ministers alike took an absorbing interest in this new island. The strong national thirst for territory manifested itself and eager mariners waited only till the new land should be cool enough to set foot on to strive who should be first to plant there his country's flag. Names in abundance were given it by successive observers,—Nerita, Sciacca, Fernandina, Julia, Hotham, Corrao, and Graham. The last holds good in English speech, and as Graham's Island it is known in books to-day, though the sea took back what it had given, leaving but a shoal of cinders and sand.

The Bay of Santorin, in the island of that name, which lies immediately to the north of Crete, has long been noted for its submarine volcanoes. According to one account, indeed, the whole island was at a remote period raised from the bottom of the sea; but this is questionable. It is, with more reason, supposed that the bay is the site of an ancient crater, which was situated on the summit of a volcanic cone that subsequently fell in. Certain it is that islands have from time to time been thrown up by volcanic forces from the bottom of the sea within this bay, and that some of them have remained, while others have sunk again.

HOW AN ISLAND GREW

Of the existing islands, some were thrown up shortly before the beginning of the Christian era; in particular, one called the Great Cammeni, which, however, received a considerable accession to its size by a fresh eruption in A. D. 726. The islet nearest Santorin was raised in 1573, and was named the Little Cammeni; and in 1707 there was added, between the other two, a third, which is now called the Black Island. This made its appearance above water on the 23rd of May, 1707, and was first mistaken for a wreck; but some sailors, who landed on it, found it to be a mass of rock; consisting of a very white soft stone, to which were adhering quantities of fresh oysters. While they were collecting these, a violent shaking of the ground scared them away.

During several weeks the island gradually increased in volume; but in July, at a distance of about sixty paces from the new islet, there was thrown up a chain of black calcined rocks, followed by volumes of thick black smoke, having a sulphurous smell. A few days thereafter the water all around the spot became hot, and many dead fishes were thrown up. Then, with loud subterraneous noises, flames arose, and fresh quantities of stones and other substances were ejected, until the chain of black rocks became united to the first islet that had appeared. This eruption continued for a long time, there being thrown out quantities of ashes and pumice, which covered the island of Santorin and the surface of the sea—some being drifted to the coasts of Asia Minor and the Dardanelles. The activity of this miniature volcano was prolonged, with greater or less energy, for about ten years.

In 1866 similar phenomena took place in the Bay of Santorin, beginning with underground sounds and slight shocks of earthquake, which were followed by the appearance of flames on the surface of the sea. Soon after there arose, out of a dense smoke, a small islet, which gradually increased until in a week's time it was 60 feet high, 200 long and 90 wide. The people of Santorin named it "George," in honor of the King of Greece. In another week it joined and became continuous with the Little Cammeni. The detonations increased in loudness, and large quantities of incandescent stones were thrown up from the crater.

About the same time, at the distance of nearly 150 feet from the coast, to the westward of a point called Cape Phlego, there rose from the sea another island, to which was given the name of Aphroessa. It sank and reappeared several times before it established itself above water. The detonations and ejection of incandescent lava and stones continued at intervals during three weeks. From the crater of the islet George, which attained a height of 150 feet, some stones several cubic yards in bulk were projected to a great distance. One of them falling on board of a merchant vessel, killed the captain and set fire to the ship.

By the 10th of March the eruptions had partially subsided, but were then renewed, and a third island, which was named Reka, rose alongside of Aphroessa. They were at first separated by a channel sixty feet deep; but in three days this was filled up, and the two islets became united.

Reference may properly be made here to Monte Nuovo and Jorullo, not that they appertain to the present subject, but that they form examples of the action of similar forces, in the one instance exerted on a lake bottom, in the other on dry land, each yielding permanent volcanic elevations in every respect analogous to those which rise as islands from the bottom of the sea.

IN THE ICELANDIC SEAS

Off the coast of Iceland islands have appeared during several of the volcanic eruptions which that remote dependency of Denmark has manifested, and at various periods in Iceland's history the sea has been covered with pumice and other debris, which tell their own tale of what has been going on, without being in sufficient quantity to reach the surface in the form of an island mass. The sea off Reykjanes—Smoky Cape, as the name means—has been a frequent scene of these submarine eruptions. In 1240, during what the Icelandic historians describe as the eighth outburst, a number of islets were formed, though most of them subsequently disappeared, only to have their places occupied by others born at a later date. In 1422 high rocks of considerable circumference appeared. In 1783, about a month before the eruption of Skaptar Jokull, a volcanic island named Nyoe, from which fire and smoke issued, was built up. But in time it vanished under the waves, all that remains of it to-day being a reef from five to thirty-five fathoms below the sea-level. In 1830, after several long-continued eruptions of the usual character, another isle arose; while at the same time the skerries known as the Geirfuglaska disappeared, and with them vanished the great auks, or gare-fowls—birds now extinct—which up to that time had bred on them. At all events, though the auks could not well have been drowned, no traces of them were seen after the date mentioned. In July, 1884, an island again appeared about ten miles off Reykjanes; but it is already beginning to diminish in size, and may soon disappear.

OFF THE COAST OF ALASKA

Elsewhere in the region of the northern seas there are other instances of the influence of the submarine forces in raising up and lowering land. The coast of Alaska is a region of intense volcanic action. In 1795, during a period of volcanic activity in the craters of Makushina, on Unalaska, and in others on Umnak Island, a volume of smoke was seen to rise out of the sea about 42 miles to the north of Unalaska, and the next year it was followed by a heap of cindery material, from which arose flame and volcanic matter, the glow being visible over a radius of ten miles. In four years the island grew into a large cone, 3000 feet above the sea-level, and two or three miles in circumference. Two years later it was still so hot that when some hunters landed on it they found the soil too warm for walking. It was named Ionna Bogoslova (St. John the Theologian), by the Russians, Agashagok by the Aleuts, and is now known to the whites of that region as Bogosloff. Mr. Dall believes that it occupies the site of some rocks that existed there as long as tradition extends.

There were additions to the cone up to the year 1823, when it became so quiescent as to be the favorite haunt of seals and sea-fowls, and, when the weather was favorable, was visited by native egg-hunters from Unalaska. During the summer of 1883 Bogosloff was again seen in eruption, as it was thought. However, on closely examining the neighborhood, it was found that the old island was undisturbed, but that there had been a fresh eruption, which had resulted in the extension of Bogosloff by the appearance of a cone and crater (Hague Volcano), 357 feet high, connected with the parent island by a low sand-spit, and situated in a spot where, the year before, the lead showed 800 fathoms of water. At the same time Augustin and two other previously quiet islands on the peninsula of Alaska began simultaneously to emit smoke, dust and ashes, while a reef running westward and formerly submerged became elevated to the sea surface. Other islands, of origin exactly similar to Bogosloff and those mentioned, are to be found in this region, notably Koniugi and Kasatochi, in the western Aleutians, and Pinnacle Island, near St. Matthew Island. Indeed, the volcano of Kliutchevsk, which rises to a height of over 15,000 feet, is really a volcanic island.

A permanent addition was made to the Aleutian group of Islands by the action of a submarine volcano in 1806. This new island has the form of a volcanic peak, with several subsidiary cones. It is four geographical miles in circumference. In 1814 another arose out of the sea in the same archipelago, the cone of which attained a height of 3,000 feet; but at the end of a year it lost a portion of this elevation.

In 1856, in the sea in the same neighborhood, Captain Newell, of the whaling bark Alice Fraser, witnessed a submarine eruption, which was also seen by the crews of several other vessels. There was no island formed on this occasion, but large jets of water were thrown up, and the sea was greatly agitated all around. Then followed volcanic smoke, and quantities of stones, ashes, and pumice; the two latter being scattered over the surface of the sea to a great distance. Loud thundering reports accompanied this eruption, and all the ships in the neighborhood felt concussions like those produced by an earthquake. These phenomena seem to have ended in the formation of some great submarine chasm, into which the waters rushed with extreme violence and a terrific roar.

Occurrences similar to this last have been several times observed in a tract of open sea in the Atlantic, about half a degree south of the equator, and between 20 and 22 degrees of west longitude. Although quantities of volcanic dross have been from time to time thrown up to the surface in this region, no island has yet made its appearance above water.

The events here described repeat on a far smaller scale similar ones which have occurred in remote ages in many parts of the ocean and left great island masses as the permanent effects of their work. We may instance the Hawaiian group, which is wholly of volcanic origin, with the exception of its minor coral additions, and represents a stupendous activity of underground agencies beneath the domain of Father Neptune.

In part, as we have said elsewhere in this work, all oceanic islands, remote from those in the shoal bordering waters of the continents, have been of volcanic or coral formation, or more often a combination of the two. No sooner does an island mass appear above or near the surface of tropical waters than the minute coral animals—effective only by their myriads—begin their labors, building fringes of coral rock around the cindery heaps lifted from the ocean floor. The atolls of the Pacific—circular or oval rings of coral with lagunes of sea-water within—have long been thought to be built on the rims of submarine volcanoes, rising to within a few hundred feet of the surface, much as coral reefs around actual islands. If the volcanic mass should subsequently subside, as it is likely to do, the minute ocean builders will continue their work—unless the subsidence be too rapid for their powers of production—and in this way ring-like islands of coral may in time rise from great depths of sea, their basis being the volcanic island which has sunk from near the surface far toward old ocean's primal floor.



CHAPTER XXXI.

Mud Volcanoes, Geysers, and Hot Springs.

Our usual impression of a volcano is indicated in the title of "burning mountain," so often employed, a great fire-spouting cone of volcanic debris, from which steam, lava, rock-masses, cinder-like fragments, and dust, often of extreme fineness, are flung high into the air or flow in river-like torrents of molten rock. This, no doubt, applies in the majority of cases, but the volcanic forces do not confine themselves to these magnificent displays of energy, nor are their products limited to those above specified. We have seen that mud is a not uncommon product, due to the mingling of water with volcanic dust, while water alone is occasionally emitted, of which we have a marked instance in the Volcan de Agua, of Guatemala, already mentioned. As regards mud flows, we may specially instance the first outflow from Mont Pelee, that by which the Guerin sugar works were overwhelmed.

The imprisoned forces of the earth have still other modes of manifestation. A very frequent one of these, and the most destructive to human life of them all, is the earthquake.

Minor manifestations of volcanic action may be seen in the geyser and the hot spring, the latter the most widely disseminated of all the resultant effects of the heated condition of the earth's interior. It is these displays of subterranean energy, differing from those usually termed volcanic, yet due to the same general causes, that we have next to consider. And it may be premised that their manifestations, while, except in the case of the earthquake, less violent, are no less interesting, especially as the minor displays are free from that peril to human life which renders the major ones so terrible.

While the largest volcanoes at times pour out rivers of liquid mud, there are volcanoes from which nothing is ever ejected but mud and water, the latter being generally salt. From this circumstance they are sometimes called salses, but they are more generally termed mud-volcanoes. Some varieties of them throw out little else than gases of different sorts, and these are called air-volcanoes.

THE GREAT MUD VOLCANO OF SICILY

One of the best known mud-volcanoes is at Macaluba, near Girgenti, in Sicily. It consists of several conical mounds, varying from time to time in their form and height, which ranges from eight to thirty feet. From orifices on the tops of these mounds there are thrown out sometimes jets of warmish water and mud mixed with bitumen, sometimes bubbles of gas, chiefly carbonic acid and carburetted hydrogen, occasionally pure nitrogen. The mud ejected has often a strong sulphurous smell. The jets in general ascend only to a moderate height; but occasionally they are thrown up with great violence, attaining a height of about 200 feet. In 1777 there was ejected an immense column, consisting of mud strongly impregnated with sulphur and mixed with naphtha and stones, accompanied also by quantities of sulphurous vapors. This mud-volcano is known to have been in action for fifteen centuries.

Very recently a small mud-volcano has been formed on the flanks of Mount Etna. It began with the throwing up of jets of boiling water, mixed with petroleum and mud, great quantities of gas bubbling up at the same time. In several of the valleys of Iceland there are similar phenomena, the boiling water and mud being thrown up in jets to the height of fifteen feet and upwards, the mud accumulating around the orifices whence the jets arise.

A mud-volcano named Korabetoff, in the Crimea, presents phenomena more akin to those of the igneous volcanoes of South America. There was an eruption from this mountain on the 6th of August, 1853. It began by throwing up from the summit a column of fire and smoke, which ascended to a great height. This continued for five or six minutes, and was followed at short intervals by two similar eruptions. There was then ejected with a hissing noise a quantity of black fetid mud, which was so hot as to scorch the grass on the edges of the stream. The mud continued to pour out for three hours, covering a wide space at the mountain's base. The mud-volcanoes on the coast of Beloochistan are very numerous, and extend over an area of nearly a thousand square miles. Their action resembles that at Macaluba.

THE MUD VOLCANO OF JAVA

There is a mud volcano in Java which is of interest as somewhat resembling the geyser in its mode of operation and apparently due to similar agencies. It is thus described by Dr. Horsfield:—

"On approaching it from a distance, it is first discovered by a large volume of smoke, rising and disappearing at intervals of a few seconds, resembling the vapors rising from a violent surf. A loud noise is heard, like that of distant thunder. Having advanced so near that the vision was no longer impeded by the smoke, a large hemispherical mass was observed, consisting of black earth mixed with water, about sixteen feet in diameter, rising to the height of twenty or thirty feet in a perfectly regular manner, and as if it were pushed up by a force beneath, which suddenly exploded with a loud noise, and scattered about a volume of black mud in every direction. After an interval of two or three, or sometimes four or five seconds, the hemispherical body of mud rose and exploded again. In the manner stated this volcanic ebullition goes on without interruption, throwing up a globular body of mud, and dispersing it with violence through the neighboring plain. The spot where the ebullition occurs is nearly circular, and perfectly level. It is covered only with the earthy particles, impregnated with salt water, which are thrown up from below. The circumference may be estimated at about half an English mile. In order to conduct the salt water to the circumference, small passages or gutters are made in the loose muddy earth, which lead to the borders, where it is collected in holes dug in the ground for the purpose of evaporation."

The mud has a strong, pungent, sulphurous smell, resembling that of mineral oil, and is hotter than the surrounding atmosphere. During the rainy season the explosions increase in violence.

There are submarine mud volcanoes as well as those of igneous kind. In 1814 one of this character broke out in the Sea of Azof, beginning with flame and black smoke, accompanied by earth and stones, which were flung to a great height. Ten of these explosions occurred, and, after a period of rest, others were heard during the night. The next morning there was visible above the water an island of mud some ten feet high. A very similar occurrence took place in 1827, near Baku, in the Caspian sea. This began with a flaming display and the ejection of great fragments of rock. An eruption of mud succeeded. A set of small volcanoes discovered by Humboldt in Turbaco, in South America, confined their emissions almost wholly to gases, chiefly nitrogen.

There is a close connection in character between mud volcanoes and those intermittent boiling springs named geysers. A good many of the mud volcanoes throw out jets of boiling water along with the mud; but in the case of the geysers, the boiling water is ejected alone, without any visible impregnation, though some mineral in solution, as silica, carbonate of lime, or sulphur, is usually present.

THE GEYSER IS A WATER VOLCANO

The phenomenon of the geyser serves in a measure to support the theory that steam is an important agent in volcanic action. A geyser, in fact, may be designated as a water volcano, since it throws up water only. It comprises a cone or mound, usually only a few feet high. In the middle of this is a crater-like opening with a passage leading down into the earth. As in the case of the volcano, the geyser cone is built up by its own action. In the boiling water which is ejected there is dissolved a certain amount of silica. As the water falls and cools this mineral is deposited, gradually building up a cup-like elevation. The basin of the geyser is generally full of clear water, with a little steam rising from its surface; but at intervals an eruption takes place, sometimes at regular periods, but more often at irregular intervals.

Among the largest and best known geysers in the world are those of Iceland, chief among them being the Great Geyser. Silica is the mineral with which the waters of this fountain are impregnated, and the substance which they deposit, as they slowly evaporate, is named siliceous sinter. Of this material is composed the mound, six or seven feet high, on which the spring is situated. On the top of the mound is a large oval basin, about three feet in depth, measuring in its larger diameter about fifty-six, and in its shorter about forty-six feet. The centre of this basin is occupied by a circular well about ten feet in diameter, and between seventy and eighty feet deep.

Out of the central well springs a jet of boiling water, at intervals of six or seven hours. When the fountain is at rest, both the basin and the well appear quite empty, and no steam is seen. But on the approach of the moment for action, the water rises in the well, till it flows over into the basin. Then loud subterranean explosions are heard, and the ground all round is violently shaken.

Instantly, and with immense force, a steaming jet of boiling water, of the full width of the well, springs up and ascends to a great height in the air. The top of this large column of water is enveloped in vast clouds of steam, which diffuse themselves through the air, rendering it misty. These jets succeed each other with great rapidity to the number of sixteen or eighteen, the period of action of the fountain being about five minutes. The last of the jets generally ascends to the greatest height, usually to about 100, but sometimes to 150 feet; on one occasion it rose to the great height of 212 feet. Having ejected this great column of water, the action ceases, and the water that had filled the basin sinks down into the well. There it remains till the time for the next eruption, when the same phenomena are repeated. It has been found that, by throwing large stones into the well, the period of the eruption may be hastened, while the loudness of the explosions and the violence of the fountain effect are increased, the stones being at the same time ejected with great force.

ERUPTION CAN BE INDUCED BY ARTIFICIAL MEANS

Geysers are found all over the island, presenting various peculiarities. In the case of one of the smaller ones, which is called Strokr, or the Churn, an eruption can be induced by artificial means. A barrow-load of sods is thrown into the crater of the geyser, with the effect of causing an eruption. The sensitiveness of Strokr is due to its peculiar form. An observer states that, "The bore is eight feet in diameter at the top, and forty-four feet deep. Below twenty-seven feet it contracts to nineteen inches, so that the turf thrown in completely chokes it. Steam collects below; a foaming scum covers the surface of the water, and in a quarter of an hour it surges up the pipe. The fountain then begins playing, sending its bundles of jets rather higher than those of the Great Geyser, flinging up the clods of turf which have been its obstruction like a number of rockets. This magnificent display continues for a quarter of an hour or twenty minutes. The erupted water flows back into the pipe from the curved sides of the bowl. This occasions a succession of bursts, the last expiring effort, very generally, being the most magnificent. Strokr gives no warning thumps, like the Great Geyser, and there is not the same roaring of steam accompanying the outbreak of the water."

The same author thus describes an eruption of the Great Geyser, which occurred about two o'clock in the morning: "A violent concussion of the ground brought me and my companions to our feet. We rushed out of the tent in every condition of dishabille and were in time to see Geyser put forth his full strength. Five strokes underground were the signal, then an overflow, wetting every side of the mound. Presently a dome of water rose in the centre of the basin and fell again, immediately to be followed by a fresh bell, which sprang into the air fully forty feet high, accompanied by a roaring burst of steam. Instantly the fountain began to play with the utmost violence, a column rushing up to the height of ninety or one hundred feet against the gray night sky, with mighty volumes of white steam cloud rolling after it and swept off by the breeze to fall in torrents of hot rain. Jets and lines of water tore their way through the clouds, or leaped high above its domed mass. The earth trembled and throbbed during the explosion, then the column sank, started up again, dropped once more, and seemed to be sucked back into the earth. We ran to the basin, which was left dry, and looked down the bore at the water, which was bubbling at the depth of six feet."

In the case of Strokr, the cause of this eruption is not difficult to understand. The narrow part of the channel is choked up by the turf and the steam, and prevented from escaping. Finally it gains such force as to drive out the obstacle with a violent explosion, just as a bottle of fermenting liquor may blow out the cork and discharge some of its contents.

Geysers are somewhat abundant phenomena, existing in many parts of the earth, while striking examples of them are found in the widely separated regions of Iceland, New Zealand, Japan and the western United States. In the volcanic region of New Zealand geysers and their associated hot springs are abundant. It was to their action that we owed the famous white and pink terraces and the warm lake of Rotomahana which were ruined by the destructive eruption of Mount Tarawera, already described.

GEYSERS OF THE UNITED STATES

The United States is abundantly supplied with hot springs, but geysers, outside of the Yellowstone region, are found only in California and Nevada. Those of California exist chiefly in Napa Valley, north of San Francisco, in a canon or defile. Their waters are impregnated not with silica, but with sulphur, and they thus approach more nearly in their character to mud-volcanoes, whose ejections are, in like manner, much impregnated with that substance. They are also, like them, collected in groups, there being no less than one hundred openings within a space of flat ground a mile square. Owing to their number and proximity, their individual energy is nothing like so violent as that of the geysers of Iceland. Their jets seldom rise higher than 20 or 30 feet; but so great a number playing within so confined a space produces an imposing effect. The jets of boiling water issue with a loud noise from little conical mounds, around which the ground is merely a crust of sulphur. When this crust is penetrated, the boiling water may be seen underneath. The rocks in the neighborhood of these fountains are all corroded by the action of the sulphurous vapors. Nevertheless, within a distance of not more than 50 feet from them, trees grow without injury to their health.

Few of these fountains, however, are regular geysers, most of them discharging only steam. From the Steamboat Geyser this ascends to a height of from 50 to 100 feet, with a roar like that of the escape from a steamboat boiler. Associated with the geysers are numerous hot springs, some clear, some turbid, and variously impregnated with iron, sulphur or alum. In Nevada the Steamboat Springs, as they are designated, exist in Washoe Valley, east of the Virginian range. They come nearer in character to the Yellowstone geysers, their waters depositing true geyserite, or silicious concretions. The Volcano Springs, in Lauder County, are also true geysers, though of small importance. The ground here is so thickly perforated by holes from which steam escapes that it looks like a cullender.

THE YELLOWSTONE GEYSERS

The most remarkable geyser country in the world, alike for the size and the number of its spouting fountains, is the Yellowstone region in the northwest part of the Territory of Wyoming, in the United States, which, by a special act of Congress, has been reserved as the Yellowstone National Park, exempt from settlement, purchase or preemption. Here nearly every form of geyser and unintermittent hot spring occurs, with deposits of various kinds, silicious, calcareous, etc. Of the hot springs, Dr. Peale enumerates 2,195, and considers that within the limits of the park—which is about 54 miles by 62 miles, and includes 3,312 square miles—as many as 3,000 actually exist. The same geologist notes the existence of 71 geysers in the area mentioned, though some of the number are only inferred to be spouting springs from the form of their basins and the character of the surrounding deposits. Of this vast collection of still and eruptive springs, between which there seems every gradation, those which do not send water into the air are, owing to the magnificent cascades which they form, often quite as remarkable as those which take the shape of geysers. The more striking of the latter may, however, be briefly mentioned.

In the Gibbon Basin is a geyser of late origin. In 1878 this consisted of two steam holes, roaring on the side of a hill, that looked as if they had recently burst through the surface; and the gully leading towards the ravine was at that date filled with sand, which appeared to have been poured out during an eruption. Dead trees stood on the line of this sand floor, and others, with their bark still remaining, and even with their foliage not lost, were uprooted hard by, everything indicating that the "steamboat vent," as it was called, was of recent formation. In 1875 it had no existence, but in 1879 the spouting spring—which first opened, it is believed, on the 11th of August in the preceding year—had "settled down to business as a very powerful flowing geyser," with a double period; one eruption occurring every half hour, and projecting water to the height of 30 feet; the main eruption occurring every six or seven days, with long continued action, and a column of nearly 100 feet.

The New Geyser in the same basin is also of quite recent origin. It consists of two fissures in the rock, in which the water boils vigorously. But there is no mound, and the rocks of the fissure are just beginning to get a coating of the silicious geyserite deposited from the water, so that it cannot long have been spouting. Again, in the Grotto Geyser—in the Upper Geyser Basin of Fire Hole River—the main or larger crater is hollowed into fantastic arches, beneath which are the grotto-like cavities from which it is named, which act as lateral orifices for the escape of water during an eruption. It plays several times in the course of the twenty-four hours, and sends a column of water sixty feet high, the eruption lasting an hour. As yet, however, the force of the water has not been sufficient, or of sufficiently long duration, to break through the arches covering the basin or crater. The Excelsior—claimed to be the largest of its order, which sent water nearly 300 feet into the air at intervals of about five hours, and of such volume as to wash away bridges over small streams below—was not, until comparatively recent years, known as a specially powerful geyser. But if it had for a time waned in importance, its immense crater, 330 feet in length and 200 feet at the widest part, shows that at a still earlier date it was a gigantic fountain. In this deep pit, when the breeze wafted aside the clouds of steam constantly arising from its surface, the water could be seen seething 15 or 20 feet below the surrounding level. Yet into the cauldron of boiling water a little stream of cold water, from the melting snow of the uplands, ran unceasingly. Since 1888 this great geyser has been inactive.

The Castle Geyser is so named on account of the fancied resemblance which its mound of white and grey deposit presents to the ruins of a feudal keep, the crater itself being placed on a cone or turret, which has a somewhat imposing appearance compared with the other geysers in the neighborhood. It throws a column usually about fifty or sixty feet high, at intervals of two or three hours, but sometimes the discharge shoots up much higher.

The Giant, in the Upper Geyser Basin, has a peculiar crater, which has been likened to the stump of a hollow sycamore tree of gigantic proportions, whose top has been wrenched off by a storm. This curious cup is broken down at one side, as though it had been torn away during an eruption of more than ordinary violence, and on this side the visitor is able to look into the crater, if he can contrive to avoid the jets which are constantly spouted from it. The periods of rest which it takes are varied, an eruption often not occurring for several days at a time; yet when it breaks out it continues playing for more than three hours, with a volume of water reaching a height of from 130 to 140 feet. In the interval little spouts are constantly in progress. Mr. Stanley saw one eruption which he calculated to have shot a column of water to the height of more than 200 feet. At first it seemed as though the geyser was only making a feint, the discharge which preceded the great one being merely repeated several times, followed by a cessation both of the rumbling noises and of the ejection of water. But soon, after a premonitory cloud of steam, the geyser began to work in earnest, the column discharged rising higher and higher, until it reached the altitude mentioned.

"At first it appeared to labor in raising the immense volume, which seemed loath to start on its heavenward tour; but it was with perfect ease that the stupendous column was held to its place, the water breaking into jets and returning in glittering showers to the basin. The steam ascended in dense volumes for thousands of feet, when it was freighted on the wings of the winds and borne away in clouds. The fearful rumble and confusion attending it were as the sound of distant artillery, the rushing of many horses to battle, or the roar of a fearful tornado. It commenced to act at 2 P. M., and continued for an hour and a half, the latter part of which it emitted little else than steam, rushing upward from its chambers below, of which, if controlled, there was enough to run an engine of wonderful power. The waving to and fro of such a gigantic fountain, when the column is at its height,

'Tinselled o'er in robes of varying hues,'

and glistening in the bright sunlight, which adorns it with the glowing colors of many a gorgeous rainbow, affords a spectacle so wonderful and grandly magnificent, so overwhelming to the mind, that the ablest attempt at description gives the reader who has never witnessed such a display but a feeble idea of its glory."

A DESCRIPTION OF THE GEYSER AT WORK

The only other geysers in this remarkable geyserland which we can spare room to notice are those known as the Giantess, the Beehive, and the Grand. The Giantess sends a column of water to the height of 250 feet. An eruption is usually divided into three periods—two preliminary efforts and a final one, divided from each other by intervals of between one and two hours, while the intervals of discharge are very long. Sometimes it does not play for several weeks. The Beehive, which is 400 feet from the Giantess, gets its name from the peculiar beehive-like cone which it has formed. The eruption is also almost unique. It is heralded by a slight escape of steam, which is followed by a column of steam and water, shooting to the height of over 200 feet. The column is somewhat fan-shaped, but it does not fall in rain, the spray being evaporated and carried off as steam—if, indeed, there is not more steam than water in the column. The duration of the discharge is between four and five minutes, and the interval between two eruptions from twenty-one to twenty-five hours.

The Grand is one of the most important in the Upper Geyser basin. Yet, unlike the Grotto, the Giant, or the Old Faithful,—so called from its frequent and regular eruptions—it has no raised cone or crater, and a much less cavernous bowl than the Giantess and other geysers. The column discharged ascends to the height of from eighty to two hundred feet, and the eruptions last from fifteen minutes to three-quarters of an hour, with intervals on an average of from seven to twenty hours. This fountain is apparently very irregular in its action, though it is just possible that when the Yellowstone geysers have been more consecutively studied, it will be found that these seeming irregularities depend on the varying supplies of water at different times of the year.

THE MAMMOTH HOT SPRINGS

The marvellous phenomena of the Yellowstone region are not confined to geyser action, hot springs of steady flow being, as above stated, exceedingly numerous. Of these the most striking are those known as the Mammoth Hot Springs, whose waters find their way through underground passages, finally flowing from an opening as the "Boiling River," which empties into the Gardiner River.

These springs are marvels of beauty. Their terraced bowls, adorned with delicate fret-work, are among the finest specimens of Nature's handiwork in the world, and the colored waters themselves are startling in their brilliancy. Red, pink, black, canary, green, saffron, blue, chocolate, and all their intermediate gradations are found here in exquisite harmony. The springs rise in terraces of various heights and widths, having intermingled with their delicate shades chalk-like cliffs, soft and crumbly, these latter being the remains of springs from which the life and beauty have departed. The great spring is the largest in the country, the water flowing through three openings into a basin forty feet long by twenty-five feet wide. From this the hot mineral waters drip over into lower basins, of gracefully curved and scalloped outline, the minerals deposited on the lips of the basin forming stalagmites of variegated hue, yielding a brilliant and beautiful effect. The terraced basins bear a close resemblance to the former New Zealand pink and white terraces, and since the annihilation of the latter are the most charming examples in existence of this rare form of Nature's artistic handiwork.

THE END