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Volcanic eruptions show that the earth is stored with combustible materials, such as coal, oil and gas. That there should be such a thing as natural gas, which needs only to be ignited to prove its capacity for burning, is one of the striking phenomena of nature. Natural gas has been discovered in several localities in our own country. Among these are Pittsburg, Pa., and Findlay, Ohio, where the supply appears to be inexhaustible, being derived from wells sunk from 1,000 to 1,500 feet.

Our illustration shows the process of lighting the gas escaping from a new well, before pipe connections are formed. The tall standpipe represents a huge gas-jet turned on, from which a volume of gas is escaping with a kind of dull roar. This could be lighted by hoisting a burning torch. The more common method is to fire at it a Roman candle. Suddenly the immense jet becomes ignited, a great flame rises, and sways and roars in the wind, and at night illumines the surrounding darkness, producing a strange, weird appearance.

Great Streams of Liquid Fire.

The form of the Hawaiian volcano named Mauna Loa, is a flattened dome, and this is its most remarkable feature. The idea of a volcano is so generally connected with the figure of a cone, that the mind at once conceives of a lofty sugar loaf ejecting fire, red-hot stones, and flowing lavas. But in place of slender walls around a deep crater, which the shaking of an eruption may tumble in, the summit of the Hawaiian volcano is nearly a plane, in which the crater, though six miles in circuit, is like a small quarry hole, the ancient orifice being not less than twentyfour miles in circumference. A violent eruption of Mauna Loa took place in the year 1843, which is thus described by the Rev. Titus Coan: On the 10th of January, just at the dawn of day, we discovered a rapid disgorgement of liquid fire from near the summit of Mauna Loa, at an elevation of about fourteen thousand feet above the sea. This eruption increased from day to day for several weeks, pouring out vast floods of fiery lava, which spread down the side of the mountain, and flowed in broad rivers, throwing a terrific glare upon the heavens, and filling those lofty mountainous regions with a sheen of light. This spectacle continued till the molten flood had progressed twenty or thirty miles down the side of the mountain, with an average breadth of one and a half miles, and across a high plain which stretches between the bases of Maunal Loa and Mauna Kea. After many weeks another missionary and myself penetrated through a deep forest, stretching between Hilo and the mountain, and reached the molten stream, which we followed to the top of the mountain, and found its source in a vast crater, amidst eternal

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snow. Down the sides of the mountain the lava had now ceased to flow upon the surface; but it had formed for itself a subterranean duct, at the depth of fifty or one hundred feet. This duct was vitrified, and down this fearful channel a river of fire was rushing at the rate of fifteen or twenty miles an hour, from the summit to the foot of the mountain. This subterranean stream we saw distinctly through several large apertures in the side of the mountain, while the burning flood rushed fearfully beneath our feet. Our visit was attended with peril and inconceiv able fatigue, but we never regretted having made it, and we returned. deeply affected with the majesty, the sublimity, the power, and the love of that God who "looketh on the earth and it trembleth, who toucheth the hills and they smoke; whose presence melteth the hills, and whose look causeth the mountains to flow down."

A Fiery Mountain of Remarkable Formation.

Mauna Loa presents the curious feature of having two distinct and seemingly unconnected craters—one on the summit of the mountain, and another on its flanks, at a much lower level. This last is named Kirauea, and is perhaps the most remarkable volcanic crater in the world. It was visited by Mr. Ellis, a missionary to those parts, who has given an account of it in his missionary tour. The approach to it lies over a vast tract completely covered with old lava; and Mr. Ellis describes his visit to it in the following terms: The tract of lava resembles in appearance an inland sea, bounded by distant mountains. Once it had certainly been in a fluid state, but appeared as if it had become suddenly petrified, or turned into a glassy stone, while its agitated billows were rolling to and fro. Not only were the large swells and hollows distinctly marked, but in many places the surface of those billows was covered by a smaller ripple, like that observed on the surface of the sea at the springing up of a breeze, or the passing currents of air, which produce what the sailors call a cat's paw. After walking some distance over the ground, which in several places sounded hollow under our feet, we at length came to the edge of the great crater, where a spectacle sublime, and even appalling, presented itself before us.

A Scene of Appalling Sublimity.

Immediately before us yawned an immense gulf, in the form of a crescent, about two miles in length, from north-east to south-west; nearly a mile in width, and apparently 800 feet deep. The bottom was covered with lava, and the south-western and northern parts of it were one vast flood of burning matter, in a state of terrific ebullition, rolling to and fro

its fiery surges and flaming billows. Fifty-one conical islands, of varied form and size, containing as many craters, rise either round the edge or from the surface of the burning lake; twenty-two constantly emitted

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VOLCANO OF TAAL LUZON-PHILIPPINES.

columns of grey smoke, or pyramids of brilliant flame; and several of these at the same time vomited from their ignited mouths streams of lava, which rolled in blazing torrents down their black indented sides into the boiling mass below.

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