We had a good climb: the total ascent being eleven hundred and thirty feet. Our native friends, used to hills, coolly walked right up the steep side, and thought nothing of it. Others of us took the more gentle ascent or were carried by our men, who enjoyed the holiday, as much as ourselves. The prospect from the summit was truly beautiful. Ivoko, we saw, was a vast crater, a quarter of a mile across; the encircling wall was complete, except at the south where the opening was fifty feet wide. The western wall is higher than the eastern. Beneath us, half a mile to the east, was another crater, Iatsífitra, second only to Ivoko, with its opening to the north. Long narrow mounds of volcanic rocks, running out from each of these hills showed the course taken by the molten lava streams. Both hills were covered inside and out with living grass. On the north-west shoulder of Ivoko were two other large craters, overhanging Betafo: two more were close by at the north-east: and others were conspicuous ten miles to the north. On the south again were several others, the horse-shoe shape being very marked in all. While ten miles to the south, was the round crater of Tritriva, with a green lake, deep down within. Far away to the east were other craters near and to the north of Sirabe. Our survey of the country had now been carried along the western districts of Imerina, and thence to the south; and it had embraced the whole country lying between the Ankárat mountains and the great ridges and peaks of Ménabé. On our former journey we had laid down the inner portions of the Vákin Ankárat; Mr. Cameron had determined the latitude of Betafo, Sirabe and Votovorona, nearly in a line; and we had examined the whole eastern side of the upper plateau from the capital to the south border of the Betsileo. At Ivoko we stood midway between these separate lines of observations: a large number of the principal peaks and positions were in sight; and we enjoyed an excellent opportunity of comparing them together, and testing the accuracy of our own work. When duly worked out, it was satisfactory to find that the sets of observations were consistent with one another, and that the discrepancies were few and within small compass. It is from these observations that our Maps have been constructed.