eness of which imagination tries to sound in shadowy
thought, like those of the grand old Eastern poem, "When the morning
stars first sang together," are, however changed in form, operative
still. The light and fragile butterfly, whose glorious garb irradiates
the summer zephyr in which it floats, has had its power of flight--which
is its power to live--determined by results of that same chain of causes
that lifted from the depths the mountain on whose sunny side he floats,
that has determined the seasons and the colour of the flower whose
nectar he sucks, and that discharges or dissipates the storm above, that
may crush the insect and the blossom in which it basked. And thus, as
has been said, it was not all a myth, that in older days affirmed that
in some mysterious way the actions and the lives of men were linked to
the stars in their courses.

Whatever may have been the manifestations of Vulcanicity at former and
far remoter epochs of our planet, and to which I shall return, in the
existing state of regimen of and upon our globe it shows itself chiefly
in the phenomena of Volcanoes and of Earthquakes, which are the
subjects of Vulcanology and of Seismology respectively, and in principal
part, also, of this Introduction.

The phenomena of hot springs, geysers, etc., which might be included
under the title of Thermopaegology, have certain relations to both, but
more immediately to Vulcanology.

Let us now glance at the history and progress of knowledge in these two
chief domains of Vulcanicity, preparatory to a sketch of its existing
stage as to both, and, by the way, attempt to extract a lesson as to the
methods by which such success as has attended our labours has been
achieved.

It will be most convenient to treat of Seismology first in order.

Aristotle--who devotes a larger space of his Fourth Book, [Greek: Peri
Kosmou], to Earthquakes--Seneca, Pliny, Strabo, in the so-called classic
days, and thence no end of writers down to about the end of the
seventeenth century--amongst whom Fromondi (1527) and Travagini (1679)
are, perhaps, the most important now--have filled volumes with records
of facts, or what they took to be such, of Earthquakes, as handed down
to or observed by themselves, and with plenty of hypotheses as to their
nature and origin, but sterile of much real knowledge.

Hooke's "Discourses of Earthquakes," read before the Royal Society about
1690, afford a curious example of how abuse of words on