Of the circumstance that the tropics must have been under a coating of ice as thick and permanent as that which now covers Greenland, the professor is evidently unaware. His explanation of the passage of the erratic boulders will alone account for those seen strewn upon the plains of India. "The boulders in Mysore, &c.," my correspondent writes to me, "are in some places piled one on the top of another in thousands, and their size is from ten to twenty feet thick. Near Chittoor I saw them scattered over a grassy plain extending for many miles, exactly as if they had been deposited by melting ice, as no doubt they were." We have to figure to ourselves ice covering these regions to a thickness of thousands of feet, the western range of mountains, running to elevations of four and five thousand feet, and in one part, namely at the Neilgherries, to over eight thousand, remaining uncovered, and it becomes quite intelligible that the boulders in question have been splintered off these heights by the intense frost, and borne on the ice eastwards and westwards to where they have been discerned. The foot of the Neilgherries approaches within forty miles of the western ocean, just where the huge boulders forming the Sacrifice Rocks, eight miles out at sea, occur. And on the other side the hillock, near Madras, named St Thomas's Mount, has arrested the passage of numbers of these erratics on their way to the eastern ocean. The professor's theory of course does not cover this condition of things within the tropics. The presence of tropical and sub-tropical vegetable and animal remains in the arctic regions forces him to allow of the transference of tropical heat to those quarters, but he has no consciousness that this entailed the corresponding transference of arctic cold to the tropics. The contortions of strata met with, the professor thinks, may have been caused by the grounding of icebergs and the passage of ice otherwise over the stratified beds (267), but so partial a cause does not suffice to account for a result I understand to be altogether general. We everywhere observe seriously disturbed strata, and it is not to be supposed that the moving masses of ice have equally been everywhere. For the greater and more decided action which has fractured the coal-seams, the more extensively the deeper down we go, and for the very serious upheavals and depressions which have continually altered the earth's levels, he appears to have no explanation to give. These are disturbances evidently to be associated together, and we see such in actual operation in equatorial countries. The centrifugal force there exerted disteuds the diameter of the earth, and as each portion of the globe may be brought to the position of the equator, it would be necessarily there subjected to the propulsion in that direction continually being effected. I cannot take leave of Professor Geikie's work without expressing the obligations under which all interested in these questions have been laid by the copious and carefully stated evidence he has produced, from his own actual observations and other reliable sources, to exhibit to us somewhat of the past history of the globe we inhabit. We must rise with wonder from the contemplation of the vast operations of which this earth is the constant scene. The ancient Aryans, drawing from what source of information open to them it is difficult to judge, have pictured to themselves constant dissolutions and re-creations, occupying lengthened ages; and we, in modern times, discern the unmistakeable traces of the like passage of events. The ice prevails and obliterates, or expels, all organized forms, vegetable and animal. The genial rays of the sun return, and all teems again with life. Some few of the animal forms may pass and re-pass, migrating when the climate became unbearable to them, and returning as it ameliorated, and some seeds may have been carried to and fro, and in this manner have perpetuated themselves. But there are multitudes in each kingdom which cannot thus have survived and evaded the pressure of the climate unfavourable to them. The cold would numb and congeal, and the heat would scorch out the vitality of all that were not in a condition so to transfer themselves. The rule in every region is an appropriate flora and fauna, inevitably, and the presumption must be strong that the productive powers of nature, in each place, raise up and stock it with all the forms of life suitable to it. When we wish to revive the fertility of arable land, we leave it to nurse and restore its energies unused as fallow. The ice age, wherein the processes of vital creation are sus pended, may possibly operate as a fallow period, after which nature, released for action, with accumulated forces, may have capacity to launch into life the superior forms, after the manner in which, in ordinary times, she is seen to bring into being the infusoria. To unlock her mysteries our course should be to suggest no other methods than such as she has herself put before us. TURNBULL AND SPEARS, PRINTERS, EDINBURGH. BY THE SAME AUTHOR. THE BIBLE; IS IT THE WORD OF GOD? THE SPEAKER'S COMMENTARY REVIEWED. About to Appear. THE LEGENDS OF THE OLD TESTAMENT Traced to their Apparent Primitive Sources. Demy 8vo. About 270 pages. Cloth, 5s. LONDON: TRÜBNER & CO., 57 AND 59 LUDGATE HILL. |