thesis, and builds a scheme of nature against nature, and against the sober interpretations of those who have best studied her works. Still more must we enter our severest protest when he dares to tell us, that organic matter must be every where the 'same,' (p. 166,)- such must be the rule in Jupiter and Sirius, we are all but certain that herbaceous and ligneous 'fibre, that flesh and blood, are the constituents of organic being in all the spheres which are the seats of life,'-' that where 'there is light, there will be eyes,'-(the matter of light is every where within the limits of sidereal space-are eyes every where ?) -'that the inhabitants of all the globes probably bear not only a general, but a particular resemblance to our own,' (p. 168,) that the whole of creative arrangements are in perfect unity,' &c. We have no softer words to explain our meaning, when we call this kind of language the raving madness of hypothetical extravagance. It is at open war with all the calm lessons of Inductive truth; and, on any interpretation we can give of it, bears on its front the stamp of folly and irreverence towards the God of nature. To give some semblance of truth to these brain-heated visions, he tries to prove that Mercury and Saturn may have the very temperature of the earth. It may be so; but we want better Even assuming the reasons for our belief than he can give us. truth of the nebular hypothesis, (and assuredly in the present state of our knowledge it is a very bold assumption,) we must believe, in all common reason, that Saturn is colder than the earth, because it has been longer thrown off from the central mass, and has had longer time to cool by radiating its heat into solar space because it is less dense than the earth, and having on that account a greater capacity for latent heat, must have a less heat of temperature-and because it receives a less supply of heat from the emanation of the sun. By like reasoning, we make it probable that Mercury is much hotter than the earth. Hence it follows, on every probable reason we can bring to bear upon the subject, that beings, organized like ourselves, could We can look not exist on either of the planets we have named. into the moon, and we believe that she has neither air nor water on her surface, and therefore cannot have any inhabitants reBut she may have inhabitants sembling ourselves in structure. some time hence,' says our author pleasantly; she may be now 'orly in an earlier stage of progress,' (p. 40 ;) seas may yet 'fill the profound hollows of her surface, and an atmosphere may spread over her,' and then the moon will become a green We think we have caught him napping and inhabited world.' here; for the progress of his worlds, on his own scheme of crea 6 6 6 tion, is from gaseous to solid, and not from solid to gaseous. But no matter, we cannot hold him fast for a moment. A new hypothesis, like a witch's broomstick, will lift him from the mire, should the one he rode before have landed him there by accident. The moon's atmosphere may, for ought we know, be pent up in her bowels; and, being let out by some geological catastrophe, may thenceforth blow good to her inhabitants, as many an ill wind has done to the inhabitants of the earth. He has a universal Fire Mist' (p. 30) to work all wonders. All worlds are made out of it by one unbending set of material laws; and all living things created in all worlds-all phenomena, material and moral-spring from the same material laws (and nothing else) by a stern physical necessity. This, in a few words, is our author's scheme of Nature. We might laugh at it, or admire it, according to our humour, in a poem like that of Lucretius; but we ought to do neither the one nor the other, when we read it in the laboured prose of an English Christian gentleman. He writes as if he were admitted to the council-chamber of the Deity, and the appointed interpreter of his Creator's will to a benighted world. But when we ask for his credentials, he can show us not so much as one letter of them; and he scorns all the vulgar means, and secondary helps, by which the greatest minds, but only after long toil, have been enabled to ascend to the conception of material laws, and to gain some feeble glimmering of their Maker's glory. We next come to the natural history of the Earth, and we rejoice to find a resting-place for our feet upon the solid rock; but we hardly look upon the things around us, before we see a fabric of marvellous complexity; and are led into speculations, some of which may be as well based as the celestial mechanics,' and others may be as unsubstantial as a nebular vision. Our geolo gical description will be short-little more than a formal enumeration of such facts as we believe to be well established; for were we to attempt details, they must, from the mere necessity of our narrow limits, be too meagre to satisfy any one who has read about geology, and too deficient in illustration to instruct those who are unacquainted with the science. Taking this principle as our guide, we may first enumerate three fundamental facts now established on good physical evidence. 1. The earth is of a spheroidal form, (were it not so all its equatorial regions must be under water,) and its equatorial and polar diameters are in the proportion of 300 to 299. These are the numbers now used in our Observatories; and they are the average results of a multitude of observations made with Kater's pendulum in many parts of the earth; and of a careful measurement of many large meridional arcs. Our author gives the numbers 230 and 229 as representing the proportion of the two diameters; but these were numbers derived by Newton theoretically from the statical condition of a revolving fluid body, and not from any previous measurements whatsoever. It was from these two latter numbers, combined with the great physical blunders already pointed out, that we were first led to refer the Vestiges' to the science gleaned at a lady's boarding-school; but its rank materialism soon undeceived us. 2. The mean density of the earth (that is, the density the earth would have, were its substance uniformly diffused through its whole mass) is represented by the number 5.66, the density of The determination of these numbers water being called 1. was the last work of M. Bailey, after he had repeated, with almost incredible labour, and with the best resources of modern science, the old experiment of Cavendish. Still they are but an approximation to the truth, and future observations may perhaps improve them.* 3. As we sink perpendicularly below the surface of the earth, the temperature continually increases. The rate must be obviously affected by local causes; but it is near enough for our present purpose to state, in round numbers, that we obtain an increase of more than 10 of Fahrenheit's thermometer for every hundred feet of sinking. Hence, if there be no interruption of this law, (and we cannot give the shadow of a reason why there should be any,) we must, at the depth of a few miles, reach a very high temperature.† Combining these three fundamental truths with other well * We have so much to find fault with in the subjects before us, that we rejoice for a moment to breathe a purer air; and we refer the reader, with the honest feelings of admiration, to the account of M. Bailey's We may private virtues and great public labours, read by Sir John Herschel to the Astronomical Society of London during the past year. here remark, that the unit of density is derived from distilled water at 62° of Fahrenheit. The density of the earth, from Cavendish's corrected computations, was 5.448. That by Professor Playfair, (from observations on Schehallion,) was 4.713. For the reason here stated, it follows that by no future improvement in machinery can mining operations be carried down to any very great depth below the surface of the earth. The limit may not have been ascertained; but, were this the proper place for it, we could point out some instances where mining operations are now carried on at a great depth, and in a temperature almost beyond the limit of human endurance compatible with health. known facts-that our lowest rocks have a structure indicating a previous condition of igneous fusion-that portions of the crust of the globe have many times been broken up and thrown into violent undulations; and that, in our own days, continental regions will sometimes rock and vibrate, and sea and land change their former levels-we readily admit the probability of a fluid condition in the inner portions of the globe. At any rate, whatever be their condition, they must be under great compression; and they have a mean density more than double that of the minerals at the surface. It is a fact, established on good evidence, that igneous matter has, during many periods, been protruded from below-that mountains have risen in succession from the sea-and injected their molten substance through the cracks and open fissures of the superincumbent strata. Many masses of granite, and other forms of igneous rock, became the solid bottom of some portions of the sea before the secondary strata were laid gradually upon them. The granite of Mont Blanc rose during a recent tertiary period. We can prove more than mere shiftings of level, and that many portions of sea and land have entirely changed their places. The rocks at the top of Snowdon are full of petrified sea shells-the same may be said of some high crests of the Alps, Pyrenees, and Andes. We have proof demonstrative that many parts of Scotland, and that all England, formed, during many ages, the solid bottom of the old sea. It may be true that the antagonist powers of nature, during the human period, have reached a kind of balance. But during all geological periods there have been such long intervals of repose, or of such gradual movements, that we can trace the history of the earth in the successive deposits formed in the waters of the sea. This is the great business of geology. But, before we begin our enumeration of such deposits, let us discharge a debt of gratitude to men like Hutton, Hall, and Playfair, who first taught us to reason well on these grand subjects of speculation. They laid a good foundation in the facts of nature, and their theoretical views were ennobled by a high philosophy. They found geology sunk under the load of a cumbrous hypothesis; but they lifted her, half drowned, from the waters, animated her by their fires, and she grew under their training to a goodly stature. If other discoverers have gone beyond them, it is but the common fortune of all advancing knowledge; and our modern geologists, while they are pursuing a new game, should bear in mind that, without such noble leaders, they never could have ventured to attack the quarry that is before them; and it would ill become them to think only of themselves, and forget the hard-bought honours of their fathers. The science of Paleontology has its limits, or it may run into endless details, like those of Botany. Those who love large views of nature will, perhaps, then leave the ranks in which they are now serving, and come back to more early speculations; and the problems arising out of the structure of the earth, and the phenomena of large mineral masses, may supply, for ages to come, matter for the investigations of chemical philosophy, and the calculations of exact science. But we must now come to our enumeration of the regular stratified deposits of the earth, beginning with the oldest. 1. Hypozoic system. We find in many parts of the world, and especially in the central ridges of mountain chains, a vast series of crystalline slates. They are called metamorphic by our countryman, Mr Lyell; and the word implies that their structure has been changed, since the time of their first formation, by the action of some mineralizing cause. This may be generally true, and we do not discuss the point; but, unfortunately, the structure does not, by itself, imply the age of a rock; because it is found, occasionally, among rocks of very different ages, which have been acted on by central heat.* What we affirm is-that such crystalline slates do exist in many cases below the oldest rocks in which organic remains have been discovered. These rocks have been called hypozoic by Phillips-a word implying that they contain no organic remains, and that they are geologically below all the rocks that do contain the traces of animal life. There are good examples of this division in Wales and Cumberland, and, we believe, also among the slates of the Grampian chain. We may remark, once for all, that our illustrations will, as far as possible, be borrowed from the British Isles. 2. Protozoic system. Following the analogy of the word, hy * On this subject, the geologists of Scotland led the way, and so nearly finished their work, that they left little to do for those who followed them. Statuary marble was formerly called primitive; but Sir James Hall made it out of pounded chalk or oyster shells. The erupted syenites of the Isle of Sky have converted a great mass of lias into a rock like statuary marble. In the Alps, beds of lias are, by the action of the central granite, converted into gneiss. Facts of this kind have led many observers into great mistakes. In some parts of Scandinavia the altered Silurian slates are converted into beds with a perfectly crystalline structure, which would formerly have been called primitive. Some of these facts have, perhaps, misled our author. On these subjects we must refer our readers to the Report of the British Association' for |