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into the earth before he ventured into unknown dispensations. Unable, experimentally, to account for any thing, he takes it for granted that he can define all things. Instead of pursuing his observations upon terra firma, where he could render a plain account of his proceedings, so that we might trace the route of his scientific researches; he gives an imaginative description of the phenomena of earth's interior structure, where no mortal has hitherto adventured : yet he expects us to receive his lucubrations as a faithful picture of that mysterious country, without furnishing a journal of his travels, or even pointing out a feasible way by which he could have reached those dreary regions.

Geometricians sometimes employ a curious manner of proof, which will answer our purpose on this occasion. When they cannot demonstrate the truth of a problem by taking another consecutive step on their wonted line of argument, they have recourse to what is technically called the reductio ad absurdum; whereby they show that any other position than that which they have laid down must be wrong, and consequently their own must be right. By tracing out every erroneous hypothesis, and reducing it to an absurdity, they establish the validity of their own proposition. Since one quantity must either agree or disagree with another, they prove its concurrence with a certain rule, by showing that any other supposition is untenable; and, therefore, since the two cannot differ, they must be similar. We think that the reductio ad absurdum will supply our want of positive proof in reasoning with cosmogonists. For we do not presume to imagine, that even if the Almighty had taken pains to instruct us in his method of creating worlds, we should have been able to understand the process, on account of our very limited faculties; nor do we profess to comprehend the summary outline afforded by Moses in the book of Genesis. Here we would remark upon the futility of those divines who have met geologists upon their own ground, in reasoning about a central fire, the bottom of the ocean, and the nature of a primeval chaos. We can find no footing in such awkward places; and we decline combating where we cannot stand. But we can rest upon the narrative of Scripture, and prove that it is solid truth, by overthrowing every antagonist who takes a more slippery position: we can show that we are right, by demonstrating that they are all in the wrong: unable and unwilling to establish any separate system of our own, we shall prove that Moses is correct, by the authorized method of reductio ad absurdum.

NEPTUNISTS.

SOME years ago, the poetical idea of Ovid, that our world was once a chaos or confused mixture of earth and water, prevailed to a considerable extent amongst every class of philosophers; and, as it seems to be generally entertained by school-boys, it probably is the current opinion of the mass of our population. Scriptural commentators, for want of a better explanation, took up the same view: so that, upon reading the first verses of the Bible with this pre-conceived notion, the phrase “without form and void” was supposed to mean an earthy paste such as the Roman poet had described; and Ovid's Metamorphosis was received as a pretty good version of real history. Werner adopted it for the ground-work of his geological system. He conjectured that all the particles of the earth's surface were once held in an aqueous solution; but that they were eventually united by chemical attraction, and precipitated by gravitation. When the primary rocks had been thus deposited, the water retired until they were consolidated. It again returned to form a new series; and this process was repeated at long intervals, accompanied by sundry catastrophes, until the whole strata were completed. His conjectures were readily entertained by other geologists, who thought to have hereby discovered the great agent by which the world was fashioned. The water thus set at liberty by the consolidation of the land, was supposed to have retired into beds of the ocean, and into vast caverns of the earth; but at the deluge they again burst forth, and overwhelmed all living creatures. Some eminent naturalists embraced this scheme, and the high name of Cuvier seemed for a time to frown down all opposition. Sundry appearances were adduced in support of the theory; and, when we were boys studying mineralogy, we gladly surrendered the primitive empire of our globe to the fabled god of the waters.

The Wernerian system suited both infidels and Christians. The former perceived how a fortuitous concourse of atoms in the primeval chaos, could be rightly moulded by the simple laws of attraction and chemical crystallization, without any need of an interposing Deity. The latter had only to imagine the “six days" of Moses to be prophetic periods of one thousand

years each, so as to afford a little time for the aqueous deposition: then Cuvier and Moses would mutually explain and corroborate each other. But when this specious theory was thoroughly investigated, and “weighed in the balance” of science, it was found to be singularly “wanting."

Astronomy has demonstrated that the great mass of our globe must be composed of heavy materials, about twice the density of granite. So, according to the laws of gravitation, the weighty materials of a fluid body would settle in the interior; the lighter substances would be next arranged in successive layers, according to their specific gravity; and the water would necessarily occupy the surface, after all the solid particles had subsided. In this case there could have been no mountains, springs, or rivers; which is directly opposed to the facts of the case and the declarations of Scripture.

Again, on the above plan, there could have been no vast hollows filled with water underneath the ground; for mere water would have been lighter than the pasty chaos, and yet it would have been supposed to settle in the interior, which is incompatible with the nature of fluids, and the laws of specific gravity.

To hold all the solid parts of our dense planet in an aqueous solution, so as to allow them a free motion for the purpose of crystallization, would have required an immense volume of water, such as we shrink from contemplating. Our present seas would probably not have sufficed to moisten the entire matter of the globe. Should it be conjectured that much of the ancient fluid has evaporated, the difficulty still remains—for where has it gone? The force of gravitation would prevent its leaving the neighbourhood of our globe.

Here we might ask a question which refers to more systems than that of Werner :-Can all minerals be dissolved and held in aqueous solution ?

We think not: and until this be proved by practical chemistry, those geological theories which include such a supposition must be regarded as ingenious trifling. Fire has melted some minerals, acids have decomposed others, and a few salts can be dissolved in water: but what are these, when compared with mountains of granite, gneiss, or micaslate? Could they be solved in water? Or, granting this possible, and supposing that we could obtain a solution of felspar, quartz, and mica; would they be precipitated and crystallized in the form of granite or of gneiss ? Decidedly not; for, if

homogeneous particles attract one another, then the component parts would form separate masses of a similar kind—such as we perceive in beds and strata of solid quartz. Besides, different substances have different gravities; and we cannot conceive how felspar, quartz, and mica should be held together in a liquid, until their particular crystallizations had taken place and united with one another.

We shall find other chemical curiosities in this system of aqueous deposition. First, with regard to the formation of primary strata, we discover the same materials to be made up into a variety of stratified and unstratified rocks, disposed upon each other in regular order, (with sundry exceptions,) instead of a vast mass of homogeneous rock, as we should expect to find in a chemical precipitation, where the particles had united. Gneiss has the same constituents as granite : why did it not form one mass with the former? How came the granite to harden before the deposition of gneiss commenced ? How were the laws of crystallization changed in the mean time? Mica-slate is composed of quartz and mica, like the foregoing; and it occasionally contains felspar in irregular masses.

How did this strange accident take place in nature's operations, by the felspar becoming so very unaccommodating as not to coalesce with its former friends ? On other occasions, felspar and quartz were so very fickle in their manæuvres, that they must needs compose a granulous porphyry! Clay-slate and hornblende seem to have been quite as capricious in their associations; whilst quartz, in order to show its perfect independence, is sometimes pleased to dwell by itself in large rocks or beds amongst other primitive strata. Really, if such curious formations took place according to the laws of physics, our chemists are yet unacquainted with the first principles of their science. Or, if the mode of nature's operation be now wholly changed, we need not hazard a conjecture upon her primeval manner of workmanship.

The affair is quite as marvellous when we consider the transition and secondary rocks, which are supposed to have originated in subsequent eras. It would, indeed, be hard to imagine where the waters retired after the primitive layers had been arranged, and how they returned laden with the material of new strata. But supposing this to have occurred, we should naturally expect the more recent depositions to be lying in a horizontal posture ; whilst, in reality, we find them lining the sides of almost perpendicular mountains ! The ocean, very good-naturedly, again

retired for a season, and left the rocky crust of the earth “prepared for supporting animal and vegetable life !” The naturalist would wonder how the creatures got there, and the agriculturist would make inquiry about the origin and nature of the soil : but such difficulties are mere trifles in the way

of modern geologists; they can easily overcome them by the allwonderful “ powers of nature."

This third calm, however, was not destined to be of everlasting continuance. The treacherous seas were not disposed to leave the anti-Mosaic vegetables and animals to enjoy their rocky soil. Another catastrophe was at hand; and the mighty ocean began to sport with her former work,-ascending the highest mountains, and breaking their crust into shreds and pieces, which she very wisely mixed with decayed vegetable and animal matter, and made them into alluvial rocks or fertile soil, as best pleased her fairy fancy. With great consideration, she also bethought herself of man's future necessities, and reserved a considerable portion of the forest debris in order to construct our coal-formations, which she also laid in a slanting position. It would be difficult to imagine where she obtained the metallic ores; (for as some of these are very heavy, we should have supposed them to have been first precipitated, and to have lain in enormous masses in the heart of the globe ;) but having procured them in some indiscoverable manner, she fused and carried them aloft to the summit of the mountains; then, boring holes in the hardest rocks, she filtered them through the open fissures. How those massive veins of porphyry, granite, trap, and serpentine, which perforate solid strata of different orders, and form caps on the summit of elevated regions, arrived at their strange destination, cannot now be ascertained; but they also are thought to have been poured from above by the prolific and all-accommodating waters. Volcanic productions, which, though of inconsiderable bulk, are found traversing mountains of very hard stone, prove a more difficult plienomenon to the Wernerian speculator ; especially when he considers how nearly they are allied to the floetz trap-rocks, to basalt, trachyte, and even to igneous porphyry !

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