f nearly all systematic works on Geology.

That which may be at present viewed as achieved and certainly
ascertained in theoretic Seismology is the clear conception of the
nature of earthquake motion; the relations to it of great sea or other
water wave commotions; the relations to it of sound waves--as to which,
however, more remains to be known; and the relations of all these to
secondary effects, tending in various ways to modify more or less the
topographic and other conditions of the land or sea bottom. And in
descriptive Seismology the present distribution of the earthquake bands
or regions of greatest seismic prevalence and activity are tolerably
ascertained, and their connection with volcanic lines and those of
elevation rendered more evident. Viewed alone, nothing can yet be said
to be absolutely ascertained as to the immediately antecedent cause or
causes of the impulse. The function of Earthquake, as part of the
cosmical machine, has become more clear, as the distinctive boundaries
between Earthquake and permanent elevation of the earth have been made
evident; and it has been seen that Earthquake, however contemporaneous
occasionally with permanent elevation, is not the cause, though it may
be one of the consequences of the same forces which produce elevation;
and thus, that an infinite number of Earthquakes, however violent, and
acting through however prolonged a time, can never act as an agent of
permanent elevation, unless, indeed, on that minute scale in which
surface elevation may arise from secondary effects, like that of the
Ullah Bund.

Much remains to be done, and much may be expected even from the
continuation, if done in a systematic and organised manner, of the
statistic record of Earthquakes in connection with those other branches
of cosmical statistics, Climatology, Meteorology, Terrestrial Magnetism,
etc., the observation of which is already, to a certain extent,
organised over a large portion of the globe.

And now let us look back for a moment to ask, How, by what mental path
of discovery, have we arrived at what we have passed in review?

The facts of Earthquakes have been before men for unknown ages "open
secrets," as Nature's facts have been well called; "but eyes had they
and saw not." Facts viewed through the haze of superstition, or of
foregone notions of what Nature _ought_ to do, cease to be facts. When,
after the great Calabrian Earthquake of 1783, the Royal Academy of
Naples sen