intense cold in other countries. After several days of progressive heat
here, on the hottest of which the thermometer probably reaches 103
degrees in the shade, a break occurs in the weather, and a thunderstorm
cools the air for a time. At Kuruman, when the thermometer stood above
84 degrees, rain might be expected; at Kolobeng, the point at which we
looked for a storm was 96 degrees. The Zambesi is in flood twice in the
course of the year; the first flood, a partial one, attains its greatest
height about the end of December or beginning of January; the second, and
greatest, occurs after the river inundates the interior, in a manner
similar to the overflow of the Nile, this rise not taking place at Tette
until March. The Portuguese say that the greatest height which the March
floods attain is thirty feet at Tette, and this happens only about every
fourth year; their observations, however, have never been very accurate
on anything but ivory, and they have in this case trusted to memory
alone. The only fluviometer at Tette, or anywhere else on the river, was
set up at our suggestion; and the first flood was at its greatest height
of thirteen feet six inches on the 17th January, 1859, and then gradually
fell a few feet, until succeeded by the greater flood of March. The
river rises suddenly, the water is highly discoloured and impure, and
there is a four-knot current in many places; but in a day or two after
the first rush of waters is passed, the current becomes more equally
spread over the whole bed of the river, and resumes its usual rate in the
channel, although continuing in flood. The Zambesi water at other times
is almost chemically pure, and the photographer would find that it is
nearly as good as distilled water for the nitrate of silver bath.

A third visit to Kebrabasa was made for the purpose of ascertaining
whether it might be navigable when the Zambesi was in flood, the chief
point of interest being of course Morumbwa; it was found that the rapids
observed in our first trip had disappeared, and that while they were