The continent of Africa is something like a dish turned upside down, having a high and flat central plateau, with a higher rim of hills surrounding it; from below which, exterially, it suddenly slopes down to the flat strip of land bordering on the sea. A dish, however, is generally uniform in shape--Africa is not. For instance, we find in its centre a high group of hills surrounding the head of the Tanganyika Lake, composed chiefly of argillaceous sandstones which I suppose to be the Lunae Montes of Ptolemy, or the Soma Giri of the ancient Hindus. Further, instead of a rim at the northern end, the country shelves down from the equator to the Mediterranean Sea; and on the general surface of the interior plateau there are basins full of water (lakes), from which, when rains overflow them, rivers are formed, that, cutting through the flanking rim of hills, find their way to the sea. Atmospheric Agents On the east coast, near Zanzibar, we find the rains following the track of the sun, and lasting not more than forty days on any part that the sun crosses; whilst the winds blow from south-west or north-east, towards the regions heated by its vertical position. But in the centre of the continent, within 5 deg. of the equator, we find the rains much more lasting. For instance, at 5 deg. south latitude, for the whole six months that the sun is in the south, rain continues to fall, and I have heard that the same takes place at 5 deg. north; whilst on the equator, or rather a trifle to northward of it, it rains more or less the whole year round, but most at the equinoxes, as shown in the table on the following page. The winds, though somewhat less steady, are still very determinable. With an easterly tending, they deflect north and south, following the sun. In the drier season they blow so cold that the sun's heat is not distressing; and in consequence of this, and the average altitude of the plateau, which is 3000 feet, the general temperature of the atmosphere is very pleasant, as I found from experience; for I walked every inch of the journey dressed in thick woollen clothes, and slept every night between blankets. The Number of Days on which Rain fell (more or less) during the March of the East African Expedition from Zanzibar to Gondokoro. 1860 Days on 1861 Days on 1862 Days on which which which rain fell rain fell rain fell