The universal geography : earth and its inhabitants

488 SOUrn AMI RAST AFUK'A.lures ill tlio Indian Ocean. Occasioniilly a cdliiniii nf smoke shoots up fi-oni thecrater, a yawning chasm 500 feet deep and over a mile in circumference. In1858 copious Ittva streams flowed down the western slopes of Kartal, encirclinglike an island a village perched on an older eruptive rock. Several other cones,some perfect, some breached, also produce a striking effect with their headlandsterminating in columnar basalt cliffs.But besides the igneous rocks, there arc also some granitic and sedimentaryformations. In many places the beach, strewn with sandy or shingly lavasmingled with ferruginous ores, is of a bright black and reddish colour, forming astriking contrast with the dazzling white of the neighbouring coral reefs. Thesecoralline masses present great differences of form in the different islands, in GreatComoro and Moheli lying close in shore, while at Mayotte they are disposed in anoval ring round the coast, with openings here and there giving access to shipping.At a certain height above the present sea-level, arc seen layers of sand and of shellsabsolutely identical with those still inhabiting the surrounding waters, andconsequently attesting upheaval in relatively recent times.The seasons are better regulated in the Comoros than in Madagascar, theislands not being large enough greatly to modifj' the system of atmosphericcurrents. The dry season, lasting uniformly from May to October, is not veryunhealthy for Europeans, thanks to the comparatively low temperature, whichoscillates between 68° and 84° F. During this period the south-eastern tradewindsprevail ; daily, however, veering round with the sun to the south and southwest.In October begins the wet and hot season, when the glass ranges from 77"^to 95° F. and when the north-west trades bring copious rains, causing a dischargeof 120 inches and upwards on the slopes of the mountains. At times the currentsfrom opposite quarters neutralise each other, producing either calms or cyclones,which, however, are never so violent as in the Mascarenhas waters.Despite the excessive rainfall caused by the north-western monsoon, GreatComoro has not a single perennial stream, all the precipitated water disappearingrapidly in the thick deposits of volcanic ashes and scoriae covering the surface.In the other islands a few rivulets wind through the verdant valleys.Such is the fertility of the volcanic soil that, before they were inhabited, theislands were completely covered with a dense forest vegetation ; but at presentnot more than one-sixth of the surface is clothed with large timber. A few formsappear to be indigenous, but the greater part have been introduced either directlyby man (European vegetables), or by the marine currents and other naturalagencies. During the southern monsoon a local counter-current occasionallycauses the upper waters to flow back, generally towards the south, and in thisway the seeds of many Malagasy plants have been brought to the archipelago.From Madagascar also comes the greater part of the insular fauna. Most ofthe species in the two regions are identical, or at least belong to the same genera.Besides one species of lemur, the group possesses a bat (ptcropiis conioreiisi-'i)whichranges thence eastwards to Australia, but is absent from Africa. There is also aspecies of black parrot allied to a form occurring in Malasia.