CHAPTER XVI 



LAKE ITASY 



MADAGASCAR is not at present one of those regions 

 of the earth where volcanic disturbances occur ; but 

 there is ample evidence, from the numerous extinct 

 craters found in various parts of the island, that at a very 

 recent period, geologically considered possibly even within the 

 occupation of the country by its present inhabitants it was 

 the theatre of very extensive outbursts of subterranean 

 energy. The whole island has not yet been examined with 

 sufficient minuteness to determine the exact extent of these 

 old volcanoes, but they have been observed from near the 

 south-east coast in South Latitude 23, and in various 

 parts of the centre of the island up to the north-west 

 and extreme north, a distance of six hundred and eighty 

 miles ; and probably a more complete survey would reveal 

 other links connecting more closely what is, as at present 

 known, only a series of isolated groups of extinct craters. 

 In the central provinces of Madagascar there are two large 

 clusters of old volcanic cones and vents : one of them in 

 about the same latitude as the capital (19 South), but 

 from fifty to seventy miles away to the west of it, in 

 the neighbourhood of Lake Itasy ; the other in the district 

 called Vakinankaratra, situated about eighty miles to the 

 south-south-west of Antananarivo, and south-west of the great 

 central mountain mass of Ankaratra. 



This second volcanic region stretches from twenty to thirty 

 miles from Antsirabe away west to Betafo and beyond it, and 

 contains numerous and prominent extinct craters, some of 

 which have been described by the graphic pen of the late Dr 

 Mullens in his " Twelve Months in Madagascar " (pp. 214-219). 

 The doctor says that he counted in this southern group about 

 sixty cones and craters. 



The Itasy just referred to is a lake situated about fifty-five 



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