idly on the brown slopes and greener levels of this aninhabited and desolate valley. I have rarely been more impressed. I was reminded of what I had read of eastern armies, whose track may be followed years after their march by ruined villages and a depopulated country,—of scenes, too, described by the prophets,-lands once populous "grown places where no man dwelleth, or son of man passeth through."—April 22, 1840.

GEOLOGY VERSUS ASTRONOMY.

Ir was remarked early in the last century by a French wit, who was also an astronomer, that when the potentates of earth ceased to quarrel about their sublunary territories, they would in all likelihood begin to dispute about the plains and mountain ranges of the moon. They would give, he said, their own names to its peaks and craters, and fall to blows for the nominal possession of some of its more prominent eminences or profounder hollows. The prediction, however, seems to be as far from its fulfilment as ever. The present war with Russia shows that the quarrels of rulers respecting their earthly territories, so far from being at an end, or nearly so, are as serious and irreconcileable as at any former period; and hitherto at least, kings and princes have left all disputes about the nomenclature of the moon's geography to be settled by the moon's geographers. The celestial map-makers have already had their quarrels on the subject. One of them named the places on the moon's surface after philosophers eminent in all the various departments of mind; another named them after the terrestrial seas and mountains which they seemed to resemble; a third, interposing, strove to give them back to the philosophers again, but struck off the former

list all philosophers save the astronomical ones; and now the moon's surface bears, in the maps at least, marks of all the three combatants. It has its Alps, and its Apennines, and its Caucasus,-its Sea of Serenity and its Sea of Storms,― its Aristarchus and its Plato,—its Tycho and its Copernicus. There is, as we may perceive, no danger of a too unbroken peace on earth regarding the condition of the moon, or of any of the other heavenly bodies, even though neither Napoleon nor Nicholas should interfere in the quarrel.

In fine, every department of science has its controversies; and it is well that it should be so. It saves the world from all danger of connivance to deceive it, on the part of scientific men, a thing which the world is somewhat prone to suspect; and proves, on the whole, the best mode of eliciting truth. There are certain stages, too, in the course of discovery, when controversy becomes inevitable. "Tempests in the State are commonly greatest," says Bacon, "when things grow to equality, as natural tempests are greatest about the equinoctia." And we find that it is so in science also. When comparatively new sciences rise, in certain departments specially their own, to assert an equality with old ones, that, when they stood alone, had been extended beyond their just limits, controversies almost always result from the new-born equality in the disputed province. In the middle

ages, for instance, there existed but one great science-theology; and, pressed far beyond its just limits, it impinged on almost every province of physical research and every department of mind. In the fifteenth and sixteenth centuries-peculiarly the ages of maritime discovery-geography rose into importance; and, after a prolonged controversy, which at one time had well-nigh crushed Columbus, it was finally established, in opposition to the findings of St Augustine and Lactantius, that the world is round, not flat, and that it has antipodes. In the sixteenth and seventeenth centuries astro

nomy became a great and solid science; and, after a still fiercer controversy than that of the geographers, it asserted a supremacy in its own special walk against Popish theologians such as Caccini and Bellarmine, and against Protestants such as Turretine. We have seen a similar controversy carried on in the present century,-which has witnessed the rise of geology, just as the fifteenth, sixteenth, and seventeenth centuries witnessed that of geography and astronomy,-between theologians who were also geologists, such as Chalmers, Sedgwick, and Sumner, and theologians who were wholly ignorant of geology, such as Granville Penn, Eleazor Lord, and Moses Stuart. And, as in astronomy and geography, the controversy may now be regarded as ultimately settled in favour of the new science, within at least the new science's own proper province. There are, however, other controversies than theological ones, which rise when, according to Bacon," things grow to equality ;" and that equality to which geology has attained with astronomy during the last fifty years may be properly regarded as the real cause of the very interesting controversy carried on at the present time between the author of the "Essay on the Plurality of Worlds," understood to be one of the distinguished ornaments of English science, and our great countryman Sir David Brewster,—a philosopher who, while supreme in his own special walk, is perhaps of all living men the most extensively acquainted with the general domain of physical science. The English writer, though he presses his argument by much too far, may be regarded as representative of the geological side; Sir David, of the astronomical.

There are, we have said, certain stages in the course of discovery at which controversy becomes inevitable; and it seems demonstrative of the fact, that the new arguments in which these controversies originate arise much about the same time, without concert or communication, in minds en

gaged in the same or similar pursuits. Had they not been originated by the man who first made them known, they would have been originated almost contemporaneously by some one else. Almost all discovery has a similar course. Adams and Le Verrier were engaged at the same time in calculating the irregularities of Uranus, and inferred from them the existence and position of the great planet, actually discovered almost simultaneously, shortly after, by Dr Galle and Professor Challis; and it is a known fact, that Mr Lassel and Professor Bond discovered on the same evening the eighth moon of Saturn, though the Atlantic flowed between them at the time. And we find a resembling simultaneousness of inference and conclusion exemplified by the work which has given occasion to the present controversy. The argument which it amplifies and expands, and, as we think, carries by much too far, and into conclusions not legitimate, was first given to the world seven years ere the appearance of this English volume, in the columns of a Scotch newspaper, and full six years in a separate work, published and rather extensively circulated both in Britain and America. And in glancing over the first edition of the "Essay on the Plurality of Worlds," we had expected—not, perhaps, taking sufficiently into account that simultaneity of thought at certain stages of acquirement to which we refer that some acknowledgment ought to have been made to the writer who had originated the argument so long before. We ascertain, however, from the second edition of the English work now before us, that its author had framed his argument for himself, independently altogether of the previously published one. "I have no wish," he says, "to lay any stress upon the originality of the views presented in the Essay. I now know that, several years ago (in 1849), Hugh Miller, in his First Impressions of England' (chap. xvii.), presented an argument from geology very much of the nature of that which I have employed; and

that the Rev. Mr Banks, in a little tract published in 1850, urged the very insecure character of the doctrine that the planets and stars are inhabited. These coincidences with my views I did not know till my Essay was not only written, but printed. As to myself, the views which I have at length committed to paper have long been in my mind." There is an error in the date given here. The argument to which the author of the Essay refers as "much of the nature" of his own, was first published, not in 1849, but in October 1846, when it appeared in the columns of the "Witness" as part of one of the chapters of "First Impressions," a work which was published in the collected form as a volume early in the following year. Essentially, however, the reference is perfectly satisfactory, and, mayhap, not wholly uninteresting, as corroborative of our position, that at certain periods, after a certain amount of fact in some new department has been acquired, inferences never drawn before come to be drawn simultaneously by minds cut off by circumstances from all intercourse with each other. The argument, as originally stated in the "Witness," we shall take the liberty to repeat, slightly abridged, not only from its bearing on one of the most curious controversies of modern times, but as it may also serve to indicate what we deem the just degree in which the inferences of astronomers regarding the inhabitability of the planets are to be qualified by the facts of the geologist.

"There is a sad oppressiveness in that sense of human littleness which the great truths of astronomy have so direct a tendency to inspire. Man feels himself lost amid the sublime magnitudes of creation, -a mere atom in the midst of infinity; and trembles lest the scheme of Revelation should be found too large a manifestation of the Divine care for so tiny an ephemera. Now, I am much mistaken if the truths of geology have not a direct tendency to restore him to his true place. When engaged some time since in perusing one of the sublimest philosophic poems of modern times, -the 'Astronomical Discourses' of Dr Chalmers,-there occurred to me a new argument that might be employed against the infidel objection which the work was expressly written to remove. The