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worn off the general surface of a river-basin. This will amount to 1 foot in 6000 years, or 1000 feet in 6,000,000 years. Those writers, therefore, who have ridiculed the idea that atmospheric waste can exercise any important effect upon the surface of the earth, will find on reflection that in reality they have not been aware of what that waste is even now doing before their eyes. At the present rate of degradation a country will have its general level lowered by a thousand feet in six millions of years; a period which most geologists will probably regard as very brief, yet which would be long enough to allow the existing continents to be almost entirely washed into the sea. It is obvious, however, that the whole surface of a country is not worn away equally ; some parts—as flat grounds, and in particular where, as M. de Beaumont justly points out, the soil is protected by vegetationmay remain unchanged for very long periods, while other portions, such as river-beds and bare rocky slopes, suffer a comparatively rapid decay. But we may apportion the waste over the region as we choose, without affecting the sum total, which is found by dividing the annual quantity of sediment removed from the basin by the number of square feet in the area of drainage. If one rock or piece of ground has suffered no loss, its share must have fallen upon some other part of the district. Thus even in an area where it may be possible to point to well preserved monuments a thousand years old or more, the river which drains that area may demonstrate that the quantity of silt annually removed is equal to a lowering of the general surface at the rate of one foot in seven hundred and thirty years, as is the case at present with the River Po. Yet there are undoubtedly parts of the region drained by this river which may have undergone no sensible change for thousands of years.
One cannot meditate upon these aspects of the subject without being led to feel that it is not easy to avoid the conclusion that at the present rate of erosion the atmospheric agents of waste are quite competent to carve out for themselves systems of deep and wide valleys, and that the present valley systems must either have been so hollowed out, or cannot have been exposed to the action of rain, frost, and streams for more than an exceedingly brief geological period. The notion that there can be extant now any of the primeval outline of the earth's surface is ridiculed by every little stream that rolls its muddy waters to the
There is one feature in the external outline of the earth's crust which is triumphantly pointed to as a demonstration that the present form of the surface is due in the main to underground influence. We refer to the existence of deep basins or cavities
among the rocks, which hold the sheets of water familiar to everybody as lakes. If these cavities are due to depressions or other movements from below, they will of course go far to support the views of those who would refer the valleys and ravines to a similar origin. And their immense numbers over the whole of the northern portion of our hemisphere will still further strengthen the cause of the Convulsionists.' It is plain that no action of mere running water could have excavated these hollows, the bottoms being deeper than the outlets. Yet an examination of them shows that, as in the case of the valleys, an immense mass of rock has been reinoved from them. Indeed, they are in this and in other respects quite comparable to valleys, with the one great distinction, that they are deeper than the channels by which their surplus waters escape. If, therefore, it could be proved that lake-basins have generally been caused by subterranean movements, the theory of the erosive origin of valleys would thereby suffer a serious blow. For the completeness and consistency of that theory some explanation must be found which will harmonise with the deductions drawn from the other parts of the existing contour of the land.
In the year 1859 two distinguished geologists, working at this subject independently, first suggested that glacier-ice had been concerned in the production of lake-basins. M. de Mortillet, in a paper read before the Geological Society of France, and again more elaborately in an excellent memoir read in the following year to the Italian Society of Natural Science, brought forward evidence to prove that the present lakes of the Alps bad had their basins scooped for them out of old alluvia by the widely-extended glaciers of the glacial period. He admitted that the basins had been originally formed by the elevatory movements which had upraised the chain of the Alps. He then argued that the hollows thus produced had been filled up with immense deposits of detritus ; that afterwards, on the setting in of the icy ages, the glaciers advanced down the valleys, and slowly ploughed out these accumulations of loose materials ; that on the final retreat of the glaciers, the basins thus scooped out were to some extent filled up again by the débris from the ice and from the sides of the valleys; but that where they were large and deep, and where the débris carried into them was proportionately small
, they have remained, and are now occupied by sheets of fresh water. So far, however, as the primary origin of rock-basins goes, this explanation contained no advance beyond previous opinion; the glaciers were supposed merely to have removed detritus from cavities originally caused by underground movements. Professor Ramsay, who had devoted
many years to the study of glacial phenomena in this country and in Switzerland, proposed an explanation which had suggested itself to his mind several years before he had heard of that of M. de Mortillet. He saw that in any attempt to account for the existence of rock-basins by calling in the agency of subterranean force, the same difficulties start up that occur when valleys are referred to a similar cause. He first suggested, in 1859, that such basins might really be entirely due to the enormous grinding power of glacier-ice. In a subsequent year he elaborated his views in a detailed memoir, in which he called attention to the significant fact that lakes are abundant in those countries which were ice-covered during the glacial period, but comparatively rare in those regions which were not so affected. He further showed that the lakes all lay on the sites of old glaciers; that they did not coincide with the line of any open fissures; that they could not each be the result of a special subsidence of the ground or of the strata ; that they could not have been hollowed out by mere running water; and that the only available explanation was that they had been slowly dug out of the solid rock by the grinding action of the vast masses of ice which moved seaward over the land during the long glacial period.
Some such explanation was necessary for the completeness of the Huttonian philosophy. The rock-basins point to some power of erosion by which deep and wide hollows can be excavated. But no such power is furnished by rivers or by the sea, nor by any of the other denuding forces save glacier-ice. Availing itself of this additional and powerful agent, the doctrine that the existing outlines of our scenery have been carved out mainly by surface action, acquires a unity and consistency which afford strong evidence in its favour. Appealing to no merely conjectural causes, nor dazzled by the stupendous magnitude of the phenomena which it has to examine and explain, the Huttonian philosophy sedulously studies the working of existing nature, and by a slow and laborious method learns to recognise in rains, frosts, and glaciers, springs, rivers, and ocean, the tools that have been used in graving the present outlines of the continents.
The controversy now waging on these subjects will undoubtedly end in the firm establishment of the truth. Those, on the one hand, who maintain the all-powerful effects of upheaval and depression, will be led to acknowledge that they have overlooked, almost despised, the less obtrusive forces; while those, on the other hand, who believe in the potency of these surface agents, will be prevented from forgetting that the movements of the earth's crust require to be recognised. When the two schools
shall have accommodated their differences, and come to a general agreement, they will be able to join amicably in writing the latest but not the least curious chapter in the long history of our planet—the story of its outer surface. Scenery will be studied by them as a part of their science, not less than the rocks beneath. The outlines of the landscape will form in their eyes as essential a part of the geological investigation of a district as do now the various formations and strata out of which the landscape has been framed. They will thus open up a new and wide avenue of approach to their science-one which will lie open to every casual wayfarer. They will attract to the study an ever-growing number of followers; they will furnish an increasing source of pleasure to hundreds of readers who have no opportunity of ever becoming geologists; and they will give to geology a fresh and powerful claim to an important share in the science-education of our schools.
í frei Art. VIII.—1. Paræmiographi Græci. Leutsch et Schneidewin.
Gottingæ, 1839-51. 2. Paræmiographi Græci. Edidit T. Gaisford, S.T.P. Oxonii,
1836. 3. Novus Thesaurus Adagiorum Latinorum.
Dr. Wilhelın Binder. Stuttgart, 1861. 4. Polydori Vergilii Urbinatis Adagia. 1498. 5. Adagiorum Opus Desiderii Erasmi. Lugduni, 1529. 6. Proverbs chiefly taken from the Adagia of Erasmus. By
Robert Bland, M.D. London, 1814. 7. A Handbook of Proverbs, comprising Ray's Collection, with
his Additions, fc. fc. Collected by H. G. Bohn. London,
1857. 8. A Polyglot of Foreign Proverbs, with Index. By H. G.
Bohn. London, 1857. 9. Proverbs, or Old Sayed Saws and Adages.
Collected by James Howell, Esq. London, 1659. 10. A Dictionary of Spanish Proverbs. By John Collins.
London, 1823 11. Quelque Six Mille Proverbes. Par le P. Ch. Cahier. Paris,
1836. 12. Petite Encyclopédie des Proverbes Français. Par Hilaire le
Gais. Paris, 1860. 13. Arabic Proverbs Translated and Erplained. By J. L. Burckhardt. London, 1830.
14. Wit and Wisdom from West Africa. Captain R. F. Burton.
London, 1865. 15. Scots Proverbs. By Allan Ramsay. Edinburgh, 1797. 16. Mavor's Proverbs, Alphabetically Arranged. London, 1804. 17. Select Proverbs of all Nations. By Thomas Fielding.
London, 1824. 18. Proverbs of all Nations, Compared, Explained, and Nlustrated.
By Walter K. Kelly. London, 1861. 19. Proverbs and their Lessons. By Richard Chenevix Trench,
D.D. Fourth edition. London, 1857.
TISDOM manifests herself in divers forms, but seldom
perhaps in any more acceptably or impressively than when she clothes herself in proverbial guise. Reading and observation leave some mark on minds of any calibre, and the result of such impression, in its most popular and perhaps most durable form, is the proverb;' the coiner of which does not indeed transmit his name with the gift of condensed wisdom he bequeaths to posterity, but in his namelessness enjoys an immortality of popular favour such as falls to the lot of few orations, or poems, or treatises. Considerations of this kind seem to justify that class of definitions of a proverb which make its essence to be wisdom in brief.'
While Aristotle speaks of Proverbs as “remnants which, on account of their shortness and correctness, have been saved out of the wreck and ruins of ancient Philosophy, Agricola declares them to be ‘short sentences into which, as in rules, the ancients have compressed life.' Quaint Thomas Fuller defined it .much matter decocted into few words;' and James Howell (a great deal of weight wrapt up in a little ;' nor is the modern definition, the wisdom of many and the wit of one,' unallied to these, if it conveys the idea that the proverb places before us in witty conciseness the pith of wisdom that has been often enunciated less compendiously. Accurate definition is always a hard matter, and, not least, the definition of a proverb. Catching one or two salient points, we are apt to overlook others. ‘Shortness, salt, and significance, noted by Howell as essential to a proverb, will, as Archbishop Trench justly remarks, apply to the epigram with equal fitness; and, as the same writer shews, brevity, point, and wit' will not make a saying a proverb without the endorsement of popular acceptance, Erasmus defines a proverb as Celebre dictum, scitâ quâpiam novitate insigne, but though the celebre dictum' is well enough, the latter part of the definition is surely not of the