discovery of the true theory of the earth; without them we should not have dreamed, perhaps, that the globe was formed at successive epochs, and by a series of different operations. They alone, in short, tell us with certainty that the globe has not always had the same envelope; we cannot resist the conviction that they must have lived on the surface of the earth before being buried in its depths. It is only by analogy that we have extended to the primary formations the direct conclusions which fossils furnish us with in respect to the secondary formations; and if we had only unfossiliferous rocks to examine, no one could maintain that the earth was not formed all at once.”[4]

The method adopted by Cuvier for the reconstruction and restoration of the fossil animals found in the plaster-quarries of Montmartre, at the gates of Paris, has served as a model for all succeeding naturalists; let us listen, then, to his exposition of the vast problem whose solution he proposed to himself. “In my work on fossil bones,” he says, “I propose to ascertain to what animals the osseous fragments belong; it is seeking to traverse a road on which we have as yet only ventured a few steps. An antiquary of a new kind, it seemed to me necessary to learn both to restore these monuments of past revolutions, and to decipher their meaning. I had to gather and bring together in their primitive order the fragments of which they are composed; to reconstruct the ancient beings to which these fragments belonged; to reproduce them in their proportions and with their characteristics; to compare them, finally, with others now living on the surface of the globe: an art at present little known, and which supposes a science scarcely touched upon as yet, namely, that of the laws which preside over the co-existence of the forms of the several parts in organised beings. I must, then, prepare myself for these researches by others, still more extended, upon existing animals. A general review of actual creation could alone give a character of demonstration to my account of these ancient inhabitants of the world; but it ought, at the same time, to give me a great collection of laws, and of relations not less demonstrable, thus forming a body of new laws to which the whole animal kingdom could not fail to find itself subject.”[5]

“When the sight of a few bones inspired me, more than twenty years ago, with the idea of applying the general laws of comparative anatomy to the reconstruction and determination of fossil species; when I began to perceive that these species were not quite perfectly represented by those of our days, which resembled them the most—I no longer doubted that I trod upon a soil filled with spoils more extraordinary than any I had yet seen, and that I was destined to bring to light entire races unknown to the present world, and which had been buried for incalculable ages at great depths in the earth.

“I had not yet given any attention to the published notices of these bones, by naturalists who made no pretension to the recognition of their species. To M. Vaurin, however, I owe the first intimation of the existence of these bones, with which the gypsum-quarries swarm. Some specimens which he brought me one day struck me with astonishment; I learned, with all the interest the discovery could inspire me with, that this industrious and zealous collector had already furnished some of them to other collectors. Received by these amateurs with politeness, I found in their collections much to confirm my hopes and heighten my curiosity. From that time I searched in all the quarries with great care for other bones, offering such rewards to the workmen as might awaken their attention. I soon got together more than had ever been previously collected, and after a few years I had nothing to desire in the shape of materials. But it was otherwise with their arrangement, and with the reconstruction of the skeleton, which could alone lead to any just idea of the species.

“From the first moment of discovery I perceived that, in these remains, the species were numerous. Soon afterwards I saw that they belonged to many genera, and that the species of the different genera were nearly the same size, so that size was likely rather to hinder than aid me. Mine was the case of a man to whom had been given at random the mutilated and imperfect remains of some hundreds of skeletons belonging to twenty sorts of animals; it was necessary that each bone should find itself alongside that to which it ought to be connected: it was almost like a small resurrection, and I had not at my disposal the all-powerful trumpet; but I had the immutable laws prescribed to living beings as my guide; and at the voice of the anatomist each bone and each part of a bone took its place. I have not expressions with which to describe the pleasure I experienced in finding that, as soon as I discovered the character of a bone, all the consequences of the character, more or less foreseen, developed themselves in succession: the feet were found conformable to what the teeth announced; the teeth to that announced by the feet; the bones of the legs, of the thighs, all those which ought to reunite these two extreme parts, were found to agree as I expected; in a word, each species was reproduced, so to speak, from only one of its elements.”[6]

While the Baron Cuvier was thus zealously prosecuting his inquiries in France, assisted by many eminent fellow-labourers, what was the state of geological science in the British Islands? About that same time, Dr. William Smith, better known as “the father of English geology,” was preparing, unaided, the first geological map of this country. Dr. Smith was a native of Wiltshire, and a canal engineer in Somersetshire; his pursuits, therefore, brought him in the midst of these hieroglyphics of Nature. It was his practice, when travelling professionally, during many years to consult masons, miners, wagoners, and agriculturists. He examined the soil; and in the course of his inquiries he came to the conclusion that the earth was not all of the same age; that the rocks were arranged in layers, or strata, superimposed on each other in a certain definite order, and that the strata, when of the same age, could be identified by means of their organic remains. In 1794 he formed the plan of his geological map, showing the superposition of the various beds; for a quarter of a century did he pursue his self-allotted task, which was at last completed, and in 1801 was published, being the first attempt to construct a stratigraphical map.

Taking the men in the order of the objects of their investigation, rather than in chronological order, brings before us the patient and sagacious investigator to whom we are indebted for our knowledge of the Silurian system. For many years a vast assemblage of broken and contorted beds had been observed on the borders of North Wales, stretching away to the east as far as Worcestershire, and to the south into Gloucester, now rising into mountains, now sinking into valleys. The ablest geologists considered them as a mere labyrinth of ruins, whose order of succession and distinctive organic remains were entirely unknown, “But a man came,” as M. Esquiros eloquently writes, “who threw light upon this sublime confusion of elements.” Sir Roderick Impey Murchison, then a young President of the Geological