body that when its normal position is disturbed in
the most infinitesimal degree no reactionary force will be developed
tending to restore it to its original position. The inventor has never
been found who could accomplish this suspension of a body to perfection.
The seismograph of to-day, however, has reached a stage of perfection
where close approximations are obtained in the records made.

CHAPTER XV.

Vesuvius Devastates the Region of Naples.

We have in other chapters described the terrible work of Mount Vesuvius
in the past, from the far-off era of the destruction of Pompeii down to
the end of the last century. There comes before us now another frightful
eruption, one of the greatest in its history, that of 1906. For thirty
years before this outbreak the mighty volcano had been comparatively
quiet, rarely ceasing, indeed, to smoke and fume, but giving little
indication of the vast forces buried in its heart. It showed some
sympathy with Mont Pelee in 1902, and continued restless after that
time, but it was not until about the middle of February, 1906, that it
became threatening, lava beginning to overflow from the crater and make
its lurid way down the mountain's side.

It was in the middle of the first week of April that these indications
rose to the danger point, the flow of lava suddenly swelling from a
rivulet to a river, pouring in a gleaming flood over the crater's rim,
and meeting the other streams that came streaming down the volcano's
rugged flank. While this went on the mountain remained comparatively
quiet, there being no explosions, though a huge cloud of volcanic ash
and cinders rose high in the air until it hung over the crater in the
shape of an enormous pine tree, while from it a shower of dust and sand,
soon to become terrible, began to descend upon the surrounding fields
and towns.

Dangerous as is Vesuvius at any time, the people of the vicinity dare
its perils for the allurement of its fertile soil. A ring of populous
villages encircles it, flourishing vineyards and olive groves extend
on all sides, and the hand of industry does not hesitate to attack its
threatening flanks. The intervals between its death-dealing throes are
so long that the peasants are always ready to dare destruction for the
hope of winning the means of life from its soil.

THE RIVERS OF LAVA.

All this locality was now a field of terror and death. Down on the
vineyards and villages poured the smothering a