over this zone on his way south.  On reaching the tropic of Capricorn in December, it is dry; and December and January are the months in which injurious droughts are most dreaded near that tropic (from Kolobeng to Linyanti).  As he returns again to the north in February, March, and April, we have the great rains of the year; and the plains, which in October and November were well moistened, and imbibed rain like sponges, now become supersaturated, and pour forth those floods of clear water which inundate the banks of the Zambesi.  Somewhat the same phenomenon probably causes the periodical inundations of the Nile.  The two rivers rise in the same region; but there is a difference in the period of flood, possibly from their being on opposite sides of the equator.  The waters of the Nile are said to become turbid in June; and the flood attains its greatest height in August, or the period when we may suppose the supersaturation to occur.  The subject is worthy the investigation of those who may examine the region between the equator and 10 Deg.  S.; for the Nile does not show much increase when the sun is at its farthest point north, or tropic of Cancer, but at the time of its returning to the equator, exactly as in the other case when he is on Capricorn, and the Zambesi is affected.*

* The above is from my own observation, together with information derived from the Portuguese in the interior of Angola; and I may add that the result of many years’ observation by Messrs. Gabriel and Brand at Loanda, on the west coast, is in accordance therewith.  It rains there between the 1st and 30th of November, but January and December are usually both warm and dry.  The heavier rains commence about the 1st of February, and last until the 15th of May.  Then no rain falls between the 20th of May and the 1st of November.  The rain averages from 12 to 15 inches per annum.  In 1852 it was 12.034 inches; in 1853, 15.473 inches.  Although I had no means of measuring the amount of rain which fell in Londa, I feel certain that the annual quantity exceeds very much that which falls on the coast, because for a long time we noticed that every dawn was marked by a deluging shower, which began without warning-drops or thunder.  I observed that the rain ceased suddenly on the 28th of April, and the lesser rains commenced about a fortnight before the beginning of November.

From information derived from Arabs of Zanzibar, whom I met at Naliele in the middle of the country, the region to the east of the parts of Londa over which we have traveled resembles them in its conformation.  They report swampy steppes, some of which have no trees, where the inhabitants use grass, and stalks of native corn, for fuel.  A large shallow lake is also pointed out in that direction, named Tanganyenka, which requires three days for crossing in canoes.  It is connected with another named Kalagwe (Garague?), farther north, and may be the Nyanja of the Maravim.  From this lake is derived, by numerous small streams, the River Loapula, the eastern branch of the Zambesi, which, coming from the N.E., flows past the town of Cazembe.