With respect to the languages spoken, I will at present make but few remarks. The Lanun and Baju are entirely different from the language of the Ida’an. I have made several vocabularies and many inquiries. At Kiau, we collected above 400 words; at Blimbing on the Limbang, 300; and whilst in Maludu Bay, seven years ago, I likewise made a short vocabulary. These three agree so far that I may say that the Ida’an and Bisaya have two out of three words in common; and on further inquiry, I think that the remaining one-third will gradually dwindle away, as at present many of the words in my Bisaya vocabulary are Malay, for which they have their native word. The result of my inquiries is that all the Ida’an speak the same language with slight local differences. We found all the tribes on the Tampasuk and Tawaran spoke fluently to each other, and one of our interpreters, who had never before visited these countries, but had been accustomed to the aborigines to the south, conversed freely with them. The Bisayas live on the rivers in the neighbourhood of the capital, and their language differs but little from that of the Ida’an. The Ida’an contains but few Malay words, these generally referring to imported articles and domestic animals. Some are similar to those of the Land Dayaks of Sarawak. I will add a few remarks on the geology of these districts, premising them, however, by the observation that I am ignorant of the science. Wherever the rocks protruded through the hills, we noticed they were decomposing sandstone; and this character continued until we reached the great mountain. Occasionally, as in Gaya island, the rocks were of a harder texture; and here a Mr. Molley is said to have been shown a vein of coal. In the districts to the west and south of the Tampasuk, we noticed no signs of primitive rock; while in the Tampasuk river, huge boulders of granite are met with a little above Butong, while the debris extends as far as the junction; but the rocks of the hills are sandstone, and this character continues to the base of the mountain. At Koung, the rocks dipped to the south-west by south, at an angle of 45°. On the Marei Parei spur, we could trace the sandstone to the height of about 4,000 feet, the dip about 80° to the south-west; greenstone immediately after protruded, and appeared to form the chief rock. On the Marei Parei spur, the compass was so affected by the peroxide of iron which formed a sort of coating to the rocks, that it would not act. The main spur consists at first of sandstone; then of shale, almost as hard as stone; and of various rocks which I could not recognize; then of decomposing granite, above which commences the massive outline of the summit. We found in our collection a piece of limestone that was broken off somewhere near the base of the mountain in the Kalupis valley.