as vague and unmeaning melodies, floating in the air around us, but conveying no definite thought, moulded into no intelligible announcement. But one passage which we have again and again caught by snatches, though sometimes interrupted and lost, at last swells in our ears full, clear, and decided; and the religious 'Hymn in honour of the Creator,' to which Galen so gladly lent his voice, and in which the best physiologists of succeeding times have ever joined, is filled into a richer and deeper harmony by the greatest philosophers of these later days, and will roll on hereafter the perpetual song' of the temple of science.

BOOK XVIII.

THE PALETIOLOGICAL SCIENCES.

HISTORY OF GEOLOGY.

Di quibus imperium est animarum, Umbræque silentes, Et Chaos, et Phlegethon, loca nocte silentia late,

Sit mihi fas audita loqui; sit, numine vestro

Pandere res alta terrâ et caligine mersas.

VIRGIL. En. vi. 264.

Ye Mighty Ones, who sway the Souls that go
Amid the marvels of the world below!

Ye, silent Shades, who sit and hear around!
Chaos! and Streams that burn beneath the ground!
All, all forgive, if by your converse stirred,
My lips shall utter what my ears have heard;
If shall speak of things of doubtful birth,
Deep sunk in darkness, as deep sunk in earth.

INTRODUCTION.

Of the Palatiological Sciences.

E now approach the last Class of Sciences which

present work,

of these, Geology is the representative, whose history we shall therefore briefly follow. By the Class of Sciences to which I have referred it, I mean to point out those researches in which the object is, to ascend from the present state of things to a more ancient condition, from which the present is derived by intelligible causes.

The sciences which treat of causes have sometimes been termed ætiological, from airía, a cause: but this term would not sufficiently describe the speculations of which we now speak; since it might include sciences which treat of Permanent Causality, like Mechanics, as well as inquiries concerning Progressive Causation. The investigations which I now wish to group together, deal, not only with the possible, but with the actual past; and a portion of that science on which we are about to enter, Geology, has properly been termed Paleontology, since it treats of beings which formerly existed.1 Hence, combining these two notions,2 Palatiology appears to be a term not inappropriate, to describe those speculations which thus refer to actual. past events, and attempt to explain them by laws of causation.

Such speculations are not confined to the world of inert matter; we have examples of them in inquiries concerning the monuments of the art and labour of distant ages; in examinations into the origin and early progress of states and cities, customs, and languages;

· Πάλαι, ὄντα.

* Πάλαι, αἰτία.