But before we bring this chapter on granite and its kindred rocks to a close, we must glance at one more purpose served by this Plutonic rock. Here is a teacup, and here is a piece of granite: the one comes from Cornwall, the other is made in Staffordshire or Worcestershire. What relation have they to each other? If it were not thought infra dig., we should say the granite is the parent of the teacup. In Cornwall, especially in the neighbourhood of St. Austel, the writer has lately visited what are called the China clay works. “The granite is here in a state of partial decomposition. In some localities, this growan” (Cornish for disintegrated granite) “is tolerably firm, when it resembles the Chinese Kaolin, and, quarried under the name of China stone, is extensively employed in the potteries. This is ready for the market when cut into blocks of a size convenient for transport; but the softer material, which is dug out of pits, and called China clay, or porcelain earth, requires a more elaborate preparation for the purpose of separating the quartz, schorl, or mica from the finer particles of the decomposed feldspar. This clay is dug up in stopes or layers, which resemble a flight of irregular stairs. A heap of it is then placed upon an inclined platform, under a small fall of water, and repeatedly stirred with a piggle and shovel, by which means the whole is gradually carried down by the water in a state of suspension. The heavy and useless parts collect in a trench below the platform; while the China clay, carried forward through a series of catch-pits or tanks, in which the grosser particles are deposited, is ultimately accumulated in larger pits, called ponds, from which the clear supernatant water is from time to time withdrawn. As soon as these ponds are filled with clay, they are drained, and the porcelain earth is removed to pans, in which it remains undisturbed until sufficiently consolidated to be cut into oblong masses. These are carried to a roofed building, through which the air can freely pass, and dried completely for the market. When dry they are scraped perfectly clean, packed in casks, and carried to one of the adjacent ports, to be shipped for the potteries.”[[24]] As furnishing some idea of the extent to which this business is carried on, it may be added that 37,000 tons of this China clay are annually shipped from the south-west of England to the potteries, the value of which is upwards of £50,000, while the number of working men and women thus employed is beyond calculation. This is one of the practical results of geology. This is one of the things which geology, once a neglected and unpopular science, has done for our comfort and welfare. “A hundred years ago, it does not seem that any part of this China clay was made use of, or that this important produce was then of any value whatever.”[[25]]

We bring this chapter to a close. Granite and its kindred rocks should stand associated with an actual history and poetry, not inferior to the history and poetry of man’s own handiwork; and we believe geology, so often regarded with dread by the uninitiated, will soon be considered worthy a patient and painstaking investigation. Remembering that geology is still an incomplete science, and that we have much yet to learn concerning the laws of organic and inorganic matter, we should be modest in the maintenance of any theory, while thankful for the acquisition of any fact. “We have yet to learn whether man’s past duration upon the earth—whether even that which is still destined to him—is such, as to allow him to philosophise with success on such matters; whether man, placed for a few centuries on the earth as in a schoolroom, has time to strip the wall of its coating and count its stones, before his Parent removes him to some other destination.”[[26]]

CHAPTER IV.
THE PALÆOZOIC PERIOD.

“In His hand are the deep places of the earth.”—David.

Trench, in his charming little book on the “Study of Words,” says of words that they are “fossil poetry.” He adds, “Just as in some fossil, curious and beautiful shapes of vegetable or animal life, the graceful fern or finely vertebrated lizard, such as now it may be, have been extinct for many thousands of years, are permanently bound up in the stone, and rescued from that perishing which would otherwise have been theirs; so in words are beautiful thoughts and images, the imagination and the feeling of past ages, of men long since in their graves, of men whose very names have perished—these, which would so easily have perished too, are preserved and made safe for ever.”

Geology is the fossil poetry of the earth; such a poetry as those can never dream of who in a pebble see a pebble and nothing more. But to those who walk through this great and beautiful world intent upon finding material for thought and reflection, there is no “picking up a pebble by the wayside without finding all nature in connexion with it;” and the most retired student, in search not simply of the picturesque or of the beautiful, but of anything and everything that can minister to his profounder worship of Him to whom belongeth both “the deep places of the earth and the strength of the hills,” may say of his solitary rambles:—

“There rolls the deep where grew the tree;—

O earth, what changes hast thou seen!

There where the long street roars, hath been

The stillness of the central sea.”[[27]]