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been, and are still taking place in many parts of the world-c.g., the coasts of Scandinavia, Greenland, Cutch, South America, Pozzuoli, &c.*
"Will the geologist declare with perfect composure that the earth has at length settled into a state of repose? Will he continue to assert that the changes of relative level of land and sea, so common in former ages of the world, have now ceased ? If, in the face of so many striking facts, be persists in maintaining this favourite dogma, it is in vain to hope that, by accumulating the proofs of similar convulsions during a series of antecedent ages, we shall shake his tenacity of purpose:t
'Si fractus illabatur orbis,
Impavidum ferient ruinæe.'”—Hor., lib. iii., ode iii. (2.) It ignores altogether the world-wide tradition of a recent great Deluge. Even if this were not universal, the forces which produced such a great catastrophe would probably more or less affect the levels of many distant parts of the earth's surface.
(3.) It is assumed that flint flakes and implements are necessarily the work of man.
(4.) Allowing them to be the work of man, are they of necessity contemporaneous with the gravel-beds in which tbey are sometimes found? How is it the bones of man are conspicuous by their absence”? Did primæval man never die ? Have these beds never been visited in subsequent ages for their rich stores of flint? What has become of the immense number of chippings of "the great gun-flint period”? Have any of them found their way into the museums of collectors amongst “undoubted relics of the great antiquity of man”? The notorious “ fossil jaw” of Amiens reminds us that great men are not infallible, and that a gravel-bed may be disturbed without its being suspected.
REMARKS BY PROFESSOR W. BOYD DAWKINS, F.R.S.
I ENTIRELY hold with Professor Hughes in the view which he takes relating to the antiquity of man, and the necessity of looking narrowly into facts
* The following remarks by Professor Huxley, made (August 22, 1879) at the meeting of the British Association, are interesting :
“The question as to the exact time to be attached to alluvial remains in the Somme Valley cannot be settled satisfactorily. Few persons except men of science are aware that there have been enormous changes during the last 500 years in the north of Europe. The volcanoes of Iceland bave been continually active, great floods of lava had been poured forth, and the level of the coast had been most remarkably changed. Similar causes might have produced enormous changes in the valley of the Somme, and therefore any arguments based as to time upon the appearances of the valley were not to be trusted.”—ED. + C. Lyell
, Principles of Geology, Sth edition, p. 450.
bearing on the question. All the alleged cases of the existence of man before the Palæolithic age, on the Continent, seem to me on a careful inquiry to be unsatisfactory. If the flints found at Thenay, and supposed to prove the existence of Meiocene man, be artificial, and be derived from a Meiocene stratum, there is, to my mind, an insuperable difficulty in holding them to be the handiwork of man. Seeing that no living species of quadruped was then alive, it is to me perfectly incredible that man, the most highly specialised of all, should have been living at that time. The flints shown in Paris by Professor Gaudry appear to be artificial; while those in the Museum of St. Germains appear to be partly artificial and partly natural, some of the former, from their condition, Laving been obviously picked up on the surface of the ground. The cuts on the Meiocene fossil bones discovered in several other localities in France may have been produced by other agencies than the hand of man.
Nor in the succeeding Pleiocene age is the evidence more convincing. The human skull found in a railway cutting at Olmo, in Northern Italy, and supposed to be of Pleiocene age, was associated with an implement, according to Dr. John Evans, of Neolithic age. Some of the cut fossil bones discovered in various parts of Lombardy, and considered by Professor Capellini to be Pleiocene, were undoubtedly produced by a cutting implement before they became mineralized, a point on wbich the examination of the specimens leaves me no reason for doubt. I do not, however, feel satisfied that the bones became mineralized in the Pleiocene age ; and the fact, that only two species of quadruped now alive then dwelt in Europe, renders it highly improbable that man was living at this time. This zoological difficulty seems to me insuperable.
The only other case which demands notice is that which is taken to establish the fact that man was living in the Interglacial age, in Switzerland. The specimens supposed to offer ground for this hypothesis consist of a feir pointed sticks in Professor Rütimeyer's collection at Basle, of the shape and size of a rather thin cigar, crossed by a series of fibres running at rightangles. They appear to me after a careful examination to present no mark of the hand of man, and to be merely the resinous knots which have dropped out of a rotten pive trunk, and survived the destruction of the rest of the tree. As the evidence stands at present there is no proof, on the Continent or in this country, of man having lived in tbis part of the world before the middle stage of the Pleistocene age, when most of the living mammalia were then alive, and when mammoths, rhinoceroses, bisons, horses and Irish elks, lions, hyænas, and bears haunted the neighbourhood of London, and were swept down by the floods of the Thames as far as Erith and Crafford.
REMARKS BY J. THORNHILL HARRISON, ESQ., F.G.S., M.I.C.E.
The author's first question is, “In what formation have we found conclusive evidence tbat man was there?"
Leaving the earlier formations, he brings within view the latest beds known to geologists, the Tertiary and Post-tertiary. These beds bear evidence of the truth of the Mosaic record, as to the creation on the sixth day, first of the mammals, then of man.
The Tertiary beds contain remains of mammals, but, as the author says, the evidence is insufficient to prove that man was there.
In the Post-tertiary beds remains of man are, for the first time, found embedded in the earth; but when within the range of this deposit was man created ? That is the question.
Lyell subdivides the Post-tertiary into Post-pliocene and Recent. The former embraces the period known as Glacial; part, often a considerable part, of the mammalia of this period belongs to extinct species ; whereas the mammalia as well as shells found in deposits of the Recent period are identical with species now living.
That man existed on the earth during the deposit of beds of the Recent period there is no question. The objects found in caves and in the Post-glacial river-gravels are admitted to be really of human workmanship. The point chiefly contested by the author is the existence of man in Glacial and Interglacial times; and upon this he says that “all the evidence is to him quite inconclusive,” at the same time he admits that traces of man with the extinct mammalia have been found in caves and Post-glacial river-gravels.
Let me ask, What evidence is there of the existence of the mammals during the Glacial period which does not equally apply to man? There is evidence of the pre-existence of the mammals, and we conclude therefore their continued existence during the Glacial period, but it by no means follows that during that period man was not co-existent. It is admitted that man lived along with the extinct mammalia, and it seems to me probable that he did so only during the Glacial period. Let this question be answered, What occasioned the extinction of the mammals, and how does man survive ?
The author says, “In the long periods of geologic time races appear and last awhile, and then are not, and a new group of living things represents them in the next succeeding age. How they went out we cannot tell. It was not by cataclysms, for they go out one by one, and the deposits tell of slow accumulation ; but more as if some gradual change over various regions of the earth made each successive place in time unsuitable for all the life that once was there."
It was not thus the mammals ceased to be; they were in man's time, but are not. There still remains, within the polar circle, undissolved throughout
many recurring generations, ice of the Glacial period. What does it record ? The sudden destruction and instantaneous preservation of numerous mammalia, which year by year released from their icebound prison, are devoured by ravenous bears and other denizens of the polar seas. Numberless tusks lie scattered over Asia, imperishable records of a sudden destruction which overtook the animals in whose heads they grew. Is it not probable that these animals and men were overwhelmed, and, it may be, frozen as those now found nearer the Pole, and that as the ice dissolved their bodies were devoured, and the tusks alone remain the record of their pre-existence ?
These did not go out one by one. By a cataclysm alone can this sudden destruction and preservation be accounted for; we do not know of any "everyday operations which are capable of producing such effects."
The author's second question is, “ Can we assign any exact numerical estimate of years since these beds were laid down ?”
He remarks, “We have to deal with facts so clear, so numerous, so widespread, and so similar everywhere, that we must at once refer them to the common ways of river denudation."
Were it necessary to refer the geological facts alluded to, to the " ways of river denudation,” the conclusion of the author “that the age of man must be a large multiple of the historic times” would possibly be inevitable; but I do not think that such necessity exists, or that such reference can explain the facts referred to.
It appears certain that man did live with the extinct mammalia during part at least of the Glacial period. During that period the atmosphere of the temperate zone would be most conducive to health and longevity; the sky cloudless, the air dry and moderately warm, the ground wetted by dew alone. (For God had not get caused it to rain on the earth.) The theory I would suggest as worthy of consideration is, that when the glaciation attained its maximum degree, the disturbance of the equilibrium of the crust was so great, owing to the enormous accumulation of ice and snow at the poles, that a cataclysm did occur, by which the ice-bound regions were plunged towards the Equator; that the ice and snow were launched from their seat; and that the consequent dashing to and fro of the waters caused a universal deluge, the deluge of the Bible, when Noah and his family, by the interposition of the Almighty, were saved, whilst the rest of mankind with the extinct mammal were overwhelmed and perished.
I cannot expect this theory to be accepted without proof ; I therefore propose to adduce some reasons for its suggestion.
The frequent reference by the author and by Lyell to instances of " depression" and "upheaval” of the surface of the earth is an admission that the earth's crust has a considerable freedom of motion vertically. Accepting this view (to a limited extent), the effect of any considerable weight added to one part of the surface would be to destroy the equilibrium of the crust, considered as a spheroidal shell, and at the weakest parts to crush it, and elevate new mountain chains, and simultaneously, by volcanic action, to force from
the interior large masses of molten matter, which distributed by water would become stratified rocks of varied thickness and of distinctive character.
The former action is exhibited during the Tertiary period by the upheaval of the Alps, Apennines, Carpathian and Himalayan ranges, and the latter operation is exemplified by the formation of newer Pliocene beds of Italy and Sicily. Respecting these Lyell says,
“ There is probably no part of Europe where the newer Pliocene formatious enter so largely into the structure of the earth's crust, or rise to such heights above the level of the sea, as Sicily. They cover nearly one half the island, and near its centre, Castogiovanni, reach an elevation of 3,000 feet."
The beds are regularly horizontal and several hundred feet in thickness, the limestone passes downwards into sandstone and conglomerate, below which are clay and blue marl. These are most interesting stratified beds, formed undoubtedly from materials disgorged by volcanic action from the interior of the earth.
During the deposition of these beds there is undoubted evidence that the Glacial period had commenced, and that the glaciation at the Pole was steadily extending.
Now what does this glaciation mean? Simply this, that the crust of the earth no longer transmitted heat sufficient to melt the snow that fell upon it; that at that period there was no diversion, as now, of vast volumes of tidal waters of high temperature from the Equator to the Pole, and that there was a gradual but steady accumulation of snow and ice in the polar regions. This accumulation implies a corresponding evaporation and abstraction of water from the equatorial regions. The result would be a simultaneous loading of the crust at the Pole, and diminution of pressure on the parts previously covered by the sea. The natural consequence would be a squeezing-out of molten matter from the interior as above referred to, and probably the simultaneous crushing of the crust and formation of mountains, or further elevation of those previously raised.
Such results would, however, in no way arrest the process of snow-aocumulation at the Pole; the higher the mass of snow became, the greater tendency would there be to extract every particle of moisture from the atmosphere, and it is difficult to conceive a limit to the process until the ocean should be dried up and all the water be collected in a frozen condition at the Pole.
I have as yet based my argument solely upon the admitted freedom of the earth's crust to move vertically. I must now suggest the probability (as I have already more fully explained in a paper presented to the Institute) of the crust of the earth being free to move horizontally on the internal mass of matter, as well as vertically, and that, when its equilibrium was destroyed by the combined accumulation of snow at the Poles and abstraction of weight unequally from the surface towards the Equator, the crust of the earth did shift its position as already suggested-reeling to and fro-by which some of the ice was thawed; it steadied again, but eventually so far shifted its position as to launch the burden of accumulated frozen materials towards the Equator,