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This eBook from the Gutenberg Project consists of approximately 126 pages of information about Scientific American Supplement, No. 388, June 9, 1883.
locality in which the eruptive phenomena were manifesting themselves was nearly the same as that which formed the theater of the celebrated eruption of 1669.  This locality overlooks an inclined plane which is given up to cultivation, and in which are scattered, at a short distance from the place of the eruption, twelve villages having a total population of 20,000 inhabitants.  On the second day the character, of the eruption had become of a very alarming character.  New fissures showed themselves up to the vicinity of Nicolosi, and the lava flowed in great waves over the circumjacent lands.  This seemed to indicate a lengthy eruption; but, to the surprise of those interested in volcanic phenomena, on the third day the eruptive movement began to decrease, and, during the night, stopped entirely.  This was a very fortunate circumstance, for this eruption would have caused immense damages.  It cannot be disguised, however, that the eruptive attendants of this conflagration remain under conditions such as to constitute a permanent danger for the neighboring villages.  It has happened, in fact, that in consequence of the quick cessation of the eruption, those secondary phenomena through which nature usually provides a solid closing of the parasitic craters have not occurred.  So it is probable that when a new eruption takes place it will be at the same point at which manifested itself the one that has just abated.—­La Nature.

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Take an ordinary wine bottle and place it in front of and within a few inches of a lighted candle.  Blow against the bottle with your mouth at about four or six inches distant from it and in a line with the flame.  Very curiously, notwithstanding the presence of the bottle and its interception of the current of air, the candle will be immediately extinguished as if there were no obstacle in the way.  This phenomenon is readily understood when we reflect that the bottle receives the current of air on its polished surface and divides it into two, one of which is guided to the right and the other to the left.  These two currents, after separating and driving back the surrounding air, meet again at the very spot at which the flame is situated, and extinguish the candle.


It is evident that the experiment can be reproduced by putting the candle behind a stove pipe, a cylinder of glass or metal, a cylindrical tin box, or any other object of the same form with a diameter greater than that of a bottle, but not having a rough or angular surface, since the latter would cause the current to be lost in the surrounding air.

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