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however incompetent he may be to reconcile their spirit and tendency to his preconceived notions of an allwise and benevolent Being. Had Mr. Townsend settled these fundamental principles, he might have spared himself and his readers the trouble of those tedious inductions, by which he labours to reconcile present appearances with the Mosaic account of the Creation and the Deluge; because every rational mind must then have believed the scriptural record, independently of all appearances whatever. He might then, too, have dispensed with the slight and obscure notices of the Jewish story which heathen writers have conveyed to us, the crude and fanciful legends of classical cosmogonies and mythology, and the absurd creeds of barbarous tribes, which, though they may present some general and remote points of resemblance to the outlines of the book of Genesis, furnish only conjectural and feeble evidence of their having proceeded from the same source. The very converse, indeed, of this latter supposition has been seriously maintained: but, granting that the impurer theogonies of subsequent periods were copied from the Mosaic writings, or borrowed from the traditions to which those writings gave rise, the question concerning the truth of the matters related still recurs, and we are left without a ray of biblical criticism to direct us to the history of the original documents. Nay, we are not distinctly apprized of some of the strongest objections which have been urged against the ascription of the books in question to Moses, and which we have more than once had occasion to examine in the long course of our professional career. We grant, indeed, that the observance of the seventh day of the week, in many countries of the world, seems to bespeak affinity with the Jewish institutions : but the leading reason, which the sacred text assigns for the hallowing of that day, is not unattended with difficulty ; since it implies a repose from labour, as if fatigue could be attributed to Omnipotence, or as if a spirit of boundless benignity required to pause in doing

good.

The analogy between the golden age and the state of Adam and Eve in Paradise is somewhat forced; at least, we cannot easily suppose that the former was suggested by the latter, since the one refers to the condition of the whole race, and the other only to the two progenitors of the stock. In the one case, also, the change from happiness to misery is represented as instantaneous; and, in the other, we have intermediate stages of blended good and evil. The golden, silver, brazen, and iron ages may, in fact, be considered as mere poetical embellishments of a very prevalent but erroneous notion, that the human race has gradually dwindled and degenerated both

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in physical and mental properties, and that “ the former days were better than these.” The other instances of coincidence, between the Mosaic account of the fall of man and the opinions and tales of antient and modern heathens, appear to us to be so faint or fanciful that they cannot be seriously maintained in the way of argument. Neither can we allow that the idea of sacrifice, with a view to propitiate the wrath of imaginary deities, is not natural to man, when placed in a state of ignorance and superstition; or that the savage practice of immolating human victims originated in a positive command from heaven. To the same exalted source the author is willing to trace the practice of paying tithe : but, at this rate, we might attribute every human institution of extensive prevalence to direct communications with the Supreme Being.

Proceeding in the same strain of reasoning, Mr. Townsend enters on the grand theme of his labours, namely, the Deluge ; and, in his accustomed manner, without stopping to inquire whether the passage which describes this event may not be interpreted allegorically, whether it may not allude to some violent but partial inundation, whether the dimensions of the ark were commensurate to the tranquil maintenance of all the land, animals and birds which were directed to occupy its compartments, whether the windows of this vessel could transmit light, and withstand the pressure of the enormous torrents from above, &c.,-he quietly appeals to the fables of antient mythology, and to the mention of a flood, of some sort, in the scattered notices which have been transmitted to us respecting the superstitions of different countries :

- Traditional reports have been collected and brought forwards by every apologist for revelation, from the first ages of Christianity to the present day, and may be referred to in Stillingfileet, Gale, and Ramsay: but independently of divine authority, the most convincing evidence is to be sought for in the records which remain engraved in the deepest mines, and on the most elevated mountains.

• In the display I am about to make of this natural evidence, scattered over the surface of the earth, I shall simply state my facts, and then examine what inferences may fairly be derived from them. And for this purpose, I shall first explore one small tract of country, that the attention of the young geologist may not be distracted by a multiplicity of objects crowding at once upon his view. When he has surveyed this island, he may be the better qualified for more lis. tant excursions, and be able to compare its strata and extraneous fossils with those of every other portion of the globe. He will be thus prepared to follow me in my general conclusion, and will be convinced that the Mosaic account of the deluge is agreeable to truth.

The strata which are particularized are those of chalk, sand, the superior polite, calcareous grit, coral rag, Kelloway rock, corn brush, forest marble, the great oolite, the inferior oolite, lyas, red ground, coal and subjacent strate; under which last are included mountain lime-stone, iron, argillaceous and siliceous schist, pudding-stone, porphyry, gneiss, micaceous schist, and granite. • Between these occasionally basalt appears, but not in the vicinity of Bath. - Such is the usual succession of strata ; but in some places the intermediate beds are wanting, and therefore at Chard the chalk and lyas meet together; and the oolite reclines in Portland on the lyas beds, but at Mells upon the mountain lime-stone.'

It is shewn that an arrangement nearly similar takes place in Wales, Ireland, and Scotland ; and that an analogous structure of the superficial parts of the globe has been observed in France, Spain, and various other countries. This simple fact, if accurately ascertained, may suggest practical results of the greatest utility, whatever be the inferences which theorists may be inclined to deduce from them. The thickness of the strata, it is admitted, is subject to great varieties, whether we compare them with one another or with themselves in different places : but an attempt is made to calculate, as nearly as it is possible, their usual thickness in the west of England, and on our southern coasts.

• The chalk has been commonly estimated at three hundred feet. At Selbourn, in Hampshire, this, by actual measurement, has been found, as Mr. White informs us, to be its thickness. On Canford Heath, in Dorsetshire, it is two hundred and eighty feet. In the Isle of Wight it has been laid open to the depth of two hundred feet; but at Slindon, near Chichester, Lord Newburgh's well is sunk three hundred and twenty feet, in chalk. At Sline House, near Warlingham, in Surrey, Mr. Banion sunk his well three hundred and twenty-six feet, through the chalk, and yet his house is not on the hill, but in the bottom. At Sanderstead the wells are three hundred and sixty feet deep. At Wimbledon six hundred feet, including the superincumbent alluvial beds. In Kent, by the assistance of my valuable friend General Donkin, I have been particularly for. tunate in procuring measurements of four wells, on the chalk ridge, near Sittingbourne. At Torry Hill, on the summit of the ridge, the well is three hundred and sixty-three feet deep, and the water rises sixty feet in the well.

A mile further on the same ridge, at Minsted, Mr. Patterson's well is three hundred and ten feet deep, and contains seven feet of water.

• Mr. Tylden's well, at Milsted, a mile lower down, is two hundred and twenty-eight feet deep, and the water rises fifty feet.

• At Sittingbourne the wells are twenty feet deep; and below Sittingbourne the springs break out.

• In all these wells, the water undoubtedly flows on the same bed of clay which appears under the chalk in the higher parts of Wiltshire.

• These wells are sunk in chalk, and the well-diggers find water before they get through the bed, that is, when the pressure of water upwards overcomes the resistance of the chalk to its ascent. This perfectly accords with the well-known laws of Hydrostatics.

• The well at Dover Castle was sunk three hundred and sixty feet through the cliff, and contained twenty-one feet of water in September, 1784. Lord Spencer's well, at Maidstone, is the same depth.

I have no doubt, therefore, that the whole thickness of the chalk stratum is more than four hundred feet. My valuable friend, Mr. Parkinson, states the upper bed at six hundred and fifty feet.'

The sand-beds, taken together, are supposed to be not less than 300 feet in thickness; the superior oolite, in some places, 20, and in others 40 feet; the calcareous grit and the coral rag seem to vary from 8 to 30 feet, cach; the Kelloway rock, from 3 to 6; the corn-brash, near Bath, does not exceed 12; the forest marble is at least 40; the great oolite, in its thickest portions, 140; the inferior oolite, about 40, and its subjacent sand not much less; the lyas (blue and white) has in some places been penetrated through 60 feet, though some of the upper beds are wanting; the red ground, comprehending its marl-beds, gritrocks, &c., has been found of various thicknesses, from 100 to 180 feet, or even more.

• Beyond the limits (says Mr. T.) which I have traced, it is not easy to ascertain the thickness of the several strata which remain hereafter to be noticed. First, because, being hard, they have not, to the same degree as the preceding strata, been subject to attrition. Secondly, because the spirit of adventure, on which deep perforations must depend, has been chiefly confined to districts, where either coal strata or the precious metals have been found.'

The natural dip of the superior strata is to the S. E., which is the prevailing inclination in almost every part of Europe : but the coal-strata dip in various directions; and, beyond them, in proceeding westward, the schistose strata either dip to the N. W. or assume a nearly vertical position. The author enters into various particulars relative to the rapidity of the dip in the several strata, as far as he has been able to determine it by accurate admeasurement; and with his domestic data he compares appearances in different parts of the world. The range or direction of the strata, as discovered by the horizontal section, is found, in this country, to be generally N. E. and S. W.; and the same observation seems to be applicable to other regions that have been geologically explored. In the more specific illustration of this latter position, the British strata again pass in review ; and the coal-fields, or elliptical

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basins basins of coal and mountain lime-stone, are enumerated and delineated with a considerable degree of interest and minuteness.

A section is next devoted to the bassetting and dislocations of the strata. The basset or crop of a stratum is its termination at the surface; and this termination, if bold, elevated, and abrupt, is called the scarp. The crop, owing to the weathering of the materials, the mouldering of an elevated scarp, the deficiency of the superior portion of a bed, &c., is not always easily detected. In mountainous countries it is remarked, that every ridge, or chain, has on one side a gentle slope, whilst the opposite is either steep or even precipitous. The angle (which) these slopes inclose depends on the tenacity of the materials which originally composed the scarp. If these are hard, the angle will be acute ; if soft, it will be proportionably obtuse. Hence it is, that even in countries which are new to him, the skilful observer will, at the greatest distance, judge what substances compose the hills and mountains which present themselves to view.

From these and other general observations, Mr. Townsend passes to the indications of the bassetting of several of our native strata, the various peculiarities attending them, and some of those striking appearances for which several writers conveniently account by the term dislocation. A register of such appearances is, at all events, desirable ; and, as Mr. Townsend usually employs the provincial terms applied to the substances described, his work may prove a very valuable guide to mineralogists who have an opportunity of surveying the tracts to which he refers. Moreover, as several of the localities specified occur in the neighbourhood of Bath and Bristol, they are readily accessible to contemplation, and may furnish agreeable occupation to the geological visitants of those much frequented places. Numerous faults in collieries are also here pointed out, and attributed to tre dislocation and disruption of strata ; as are the fissures and caverns in mountain lime-stone, detached bowlders of granular quartz, fragments of granite, &c. Mr. Townsend is particularly sollicitous to prove that such blocks have not been detached by common land-floods, or torrents : but may they not have resulted from the decomposition of the softer maiters in which they were originally involved ? That precipitous mountains and abrupt cliffs are the effect of some violent disruption of their former continuity may, or may not, be consistent with fact : but we can also conceive that their present appearance may be that of their original formation, whether they proceeded from volcanic fire, or from other causes which our limited faculties are inadequate to explain. Even the circumstance of encrini, and the relics of corals which now

affect

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