As a country showing numerous traces of volcanic disturbance, Madagascar is almost every year visited by shocks of earthquake. Happily these are not of a severe character, and little damage is usually done; although often a strange subterranean roar accompanies them and a tremor of several seconds’ duration. The Malagasy still remember a rather severe earthquake which happened many years ago and detached a large mass of rock from the cliffs on the precipitous west side of the ridge on which Antanànarìvo is built. In September 1879 a severe shock, felt most in the Vònizòngo district, was experienced, and lasted for at least thirty seconds; this was accompanied by a loud rumbling sound, as of violent thunder, and in places the ground was split up by the shaking. In the year 1897, again, slight shocks were very numerous, and on some days and nights the earth appeared to have been in a constant state of tremor. These earth movements were felt more especially in the region of old volcanic disturbance about Lake Itàsy, where hundreds of slight shocks were experienced during seven or eight months. On the night of 2nd November four or five sharp movements occurred, one of which was more violent than anything remembered by the Malagasy, and wakened the whole population of the capital and around it in alarm. Chimney-stacks were thrown down, walls were cracked and ceilings damaged. This earthquake appears to have been felt over a very wide extent of country, from Tamatave and the east coast to Mèvatanàna away north-west, and as far as the Bétsiléo province in the south. It had the effect of stopping temporarily the mineral spring at Antsìrabé, which is so exactly like Vichy water; although, curiously enough, the hot-water springs, within a few yards of the other, were not affected. In the Ifànja marsh, a few miles from Itàsy, a small mud geyser is said to have appeared.
I will conclude this chapter, in which much has been said of extinct forms of existence, by a glimpse at the ancient animal life of the island. Let us try to sum up these in a few sentences.
GLIMPSES OF THE PAST
It seems probable that Madagascar, when the first representatives of mankind occupied it, was a country much more fully covered by lakes and marshes, and also by forest, than it is at present. In these waters, amid vast cane-brakes and swamps of papyrus and sedge, wallowed and snorted herds of hippopotami; huge tortoises crawled over the low lands on their margins; tall ostrich-like birds, some over ten feet high, and others no larger than bustards, stalked over the marshy valleys; great rails hooted and croaked among the reeds, and clouds of large geese and other water-fowl flew screaming over the lakes; on the sand-banks crocodiles lay by scores basking in the sun; great ape-like lemurs climbed the trees and caught the birds; troops of river-hogs swam the streams and dug up roots among the woods; and herds of slender-legged zebu-oxen grazed on the open downs. These were the animals which the first wild men hunted with their palm-bark spears, and shot with their arrows tipped with burnt clay or stone.[25]
And as we look further back through long-past geological ages, when the clays and sandstones of the oolite, and the white masses of the chalk were being deposited in the coral-studded tropic seas and archipelagoes of Europe and other parts of the world, and when Madagascar was probably no island, but a peninsula of Eastern Africa, the mist opens for a moment, and we see vast reptile forms dimly through the haze; great slender-snouted gavials in the streams and lakes, sloths moving slowly along the branches of the trees, and huge dinosaurs, sixty to eighty feet long, crawling over the wooded plains, and tearing down whole trees with their powerful arms.
Such are some glimpses of the Madagascar of the past which the study of its rocks and fossils already opens to the mental eye. We may confidently look for further light upon the dim and distant bygone ages as we learn more of the geology of the country. The thick curtain which at present shrouds the old-world times will be yet more fully lifted, and we shall probably, ere many more years have passed, be able to draw many more mental pictures of the extinct animal life of the great African island.
[23] See “Recherches sur les Lémuriens disparus et en particulier sur ceux qui vivaient à Madagascar.” Par G. Grandidier. Nouv. Arch. du Muséum, 4e série, tome vii., 144 pp. 1905. Also “On Recently Discovered Subfossil Primates from Madagascar.” By Herbert F. Standing, D.Sc. Trans. Zool. Soc., vol. xviii., pt. ii., pp. 59-217. May 1908.
These extinct lemuroids have been classed in the following genera:—Megaladapis (3 sp.), Lemur (2 sp.), Palæopropithecus (4 sp.), Archæolemur (2 sp.), Poradylemur (1 sp.), Hadropithecus (1 sp.), Mesopropithecus (1 sp.), and Archæoindris (1 sp.).
[24] No rocks of the Primary formations have been discovered in Madagascar, nor does it seem probable that any exist.