The Bridgeport evening farmer., 1910-06-24
BIRTH OF 4 VOLCANO,
Natures Process In Forming a
 Mountain of Lava.
THE FORCE OF AH ERUPTION.

UPheavaI That Destroyed the East
 Indian Island of krakatoa In 1883
 Propelled an Air Wave Three and a
 Half Times Round the Earth.
 Though volcanoes are often spoken of as burning mountains, they do not burn at all. nor. in the proper sense of the word. are they mountains at all. A volcano is really flaw in the crust of the earth through which the fierce glowing heat lying below the crust has managed to burst hole. Through this hole great Hoods of melted rock spout up. Some volcanoes work at inter- vals; some are ip eruption all the time
 As the melted rock jets up into the air and falls it naturally builds itself into mountain round the hole. The next eruption has to burst it's way The chimney it spouts through is usu- ally called "the pipe.'
 Sometimes aD eruption is so fierce that when the lava (another name for melted rock, spOuts out it is burst into bits When it falls it is sometimes as fine as dust, sometimes the size of cin- ders. Most volcanoes. indeed. are sim- ply gigantic ciDder heaps.
 When the force is not so great the lava in the pipe simply bubbles over and flows down the sides of the noun tain. exactly as pOrridge boils over the edge of pot. As lava is liquid, the slope of a lava volcano Cor lava cone, as it is usually called, is always very gentle. Falling cinders. on the other hand. pile themselves up quite steeply. A lava cone. then, is always less steep than cinder cone
 And a volcano never burns. What looks Ike flame is only the glow of the white hot lava on the clouds of steam. The more steam there is fore ing its way up the pipe the more the lava bubbles. just as in the case of the porridge. If the pressure of steam is very great. then you have the lava blown to bits and falling as cinders, w.>iIe the mighty clouds of steam rise high above the mountain. 1t is this steam that is mistaken for smoke.
 Sometimes cone sends out lava and cinders alternately. so that you have a great mountain of cinders bound to- gether by layers and walls of lava.
 These walls of lava are due to the fact that sometimes more lava wants to come up the pipe than the pipe will hold, so the lava bursts its way out through weak spots in the sides of the mountain. Etna has no fewer than TOO of these cones on it's sloHes. One of them. Monte Rossi, is hill in itself. being 45O feet high. Indeed. a model of Etna looks as if it were cov- cred with pimples.
 When Etna is really reused it is far more dangerous than Vesuyius. In 116e it nearly destroyed the city of Catania, killing 15.000 people. In 1869 it found its pipe so inconveniently small that it had to crack one of its sides. This crack was no less than twelve miles long. At the bottom white hot lava could dimly be seen through the clouds of steam. In 1755 millions of gallons of boiling water were shot out of the Val del Bove. which is a great circular pit on the slope of the mountain, four or five miles in diameter, its sides being cliffs nearly a mile high in places.
 The greatest volcanic eruption ever known took place in the East Indies fin 1883. The story makes almost tn- credible reading. The volcanic island of Krakatoa commenced proceedings by blowing half of itself into thin air. From the opening no less than a cubic mile of rock was shot out.
 A column of steam and lava dust rose into the air to a height six times as great as that of Mount Everest. It spread and spread till for hundreds of miles around the air was black as mid night. Sounds as of distant cannonad- ing were heard 2.OOO miles of.
 Sea waves fifty feet high killed 35,- 900 people and were felt as far off as California. Instead of an island half mile high there was now a hole quarter of a mile deep. The shock of the eruption sent air waves three and half times around the earth. The fine dust in the upper atmosphere add ed for months afterward strange glow to the sunsets in England and did not vanish completely for three years.
 The exact cause of the erupt1ons is not known for certain A popular the ory is that they are caused by water getting in to the white hot mass which is supposed to lie under the outer crust of the earth And it is certainly fact that practically all volcanoes are close to the edge of the sea.
 Some lava flows slowly. some quick ly. Vesuvius in 1895 sent out lava stream that in four minutes had reach ed a spot four miles off. The size of a lava stream is sometimes gigantic. In 17S3 SEaptar Jokull in Iceland emitted two streams at one time. One was forty miles long by seven miles broad. the other fifty miles by fifteen. The average depth of both was about hundred feet.
 Lava cools very, very slowly. except on the surface. which cools at once. It is an extremely bad conductor of