connected with volcanic agency, and to speculate on their causes
and modes of operation. Some also, on reaching their manhood, may
be induced to ascend one or more of the nearer active volcanoes,
and examine their phenomena for themselves. The facilities of
travel are now so great, that a visit to Vesuvius or Etna is no
longer beyond the limits of a holiday trip. Even the more remote
Hecla with the playful Geysers may be reached within a reasonable
time. Perhaps a very few, who are now scientific travellers in
embryo, may call to remembrance what they may have read in these
pages, when, many years hence, they may be climbing the cone of
Cotopaxi, or peering into the crater of Kilauea.

Apart from these considerations, a perusal of this work may enable
the young mind to form a more lively idea of the tremendous energy
of the forces which are imprisoned in the bowels of the earth. Such
a vivid conception will naturally lead to a higher appreciation of
the wisdom and power of Him who guides the operation of those
forces by his laws, and has set bounds to their activity which they
cannot overpass.



CONTENTS.


CHAPTER I.

Volcanoes in general--Origin of the Name--General Aspect--Crater--
Cone--Subordinate Cones and Craters--Peak of Teneriffe--Lava-
Streams--Cascades and Jets of Lava--Variations in its Consistency--