This very principle was made practical use of in a mechanical contrivance invented to make paper pulp out of common cane, such as the farmer’s boy delights in for a fishing pole. The hard, woody fibre was placed in a powerful iron cylinder full of water. A strong lid being adjusted, the whole was heated far above the boiling point of water. Naturally, every cell would be forced full of moisture by the immense pressure. After some hours heating, the lid was suddenly removed, and by the sudden expansion of the water into steam the cane was blown to atoms.
CRATER OF ORIZABA.
A beautiful product of the volcano of Kilauea is the substance known as “Pele’s Hair.” Small particles of glass shot violently into the air leave behind them long, glittering filaments, like gossamers. Birds often build their nests of these beautiful threads. Man, taking a hint from nature, has learned to manufacture the glass hair for himself by passing jets of steam through the molten slag of iron furnaces. It much resembles cotton wool, and is used for packing boilers and piston-heads, and similar purposes.
The appearance of fire at the summit of a volcano is rarely ever real flame. Any who has seen the peculiar appearance occasioned by brilliant illumination on a moist or foggy evening may readily perceive the cause. The phenomenon popularly known as the “sun drawing water” is of the same character. The immense cloud of vapor ascending from the volcano glows with the light sent up from the molten mass below. So it may be seen brilliant by night, and only a dark cloud by day. Stromboli has been called the light-house of the Mediterranean. In constant action, the brilliant light at night slowly fades: then suddenly breaks out as bright as before. This alternating results from the bursting of bubbles in the crater, which expose a new, hot surface. This rapidly cools; then another bubble bursts; and so the process continues. This may have suggested the alternating light now in common use in great light-houses.
In the Galapagos, and other volcanic islands of the Pacific, occurs another curious feature of volcanic action. Some places abound in seeming mounds or domes, which may be sometimes readily broken in with a heavy stone. These are produced by bubbles which partially cooled, when the lava below found some rent or outlet in another quarter and flowed away, leaving the solidified bubble.
Sometimes the cavern left by the retreating lava abounds in strange beauties. A sailor, who with a comrade, explored one of these volcanic caverns, gives the following account of it: