of Mount Njongone to the north of
Zomba, and the cook was directed to use a couple of spoonfuls of the
paste; but, instead of doing so, he put in the whole potful. The soup
tasted rather hot, but we added boiled rice to it, and, being very
hungry, partook freely of it; and, in consequence of the overdose, we
were delayed several days in severe suffering, and some of the party did
not recover till after our return to the ship. Our illness may partly
have arisen from another cause. One kind of cassava (_Jatropha maligna_)
is known to be, in its raw state, poisonous, but by boiling it carefully
in two waters, which must be thrown off, the poison is extracted and the
cassava rendered fit for food. The poisonous sort is easily known by
raising a bit of the bark of the root, and putting the tongue to it. A
bitter taste shows poison, but it is probable that even the sweet kind
contains an injurious principle. The sap, which, like that of our
potatoes, is injurious as an article of food, is used in the "Pepper-pot"
of the West Indies, under the name of "Cassereep," as a perfect
preservative of meat. This juice put into an earthen vessel with a
little water and Chili pepper is said to keep meat, that is immersed in
it, good for a great length of time; even for years. No iron or steel
must touch the mixture, or it will become sour. This "Pepper-pot," of
which we first heard from the late Archbishop Whately, is a most
economical meat-safe in a hot climate; any beef, mutton, pork, or fowl
that may be left at dinner, if put into the mixture and a little fresh
cassereep added, keeps perfectly, though otherwise the heat of the
climate or flies would spoil it. Our cook, however, boiled the cassava
root as he was in the habit of cooking meat, namely, by filling the pot
with it, and then pouring in water, which he allowed to stand on the fire
until it had become absorbed and boiled away. This method did not expel
the poisonous properties of the root, or render it wholesome; for,
notwithstanding our systematic caution in purchasing only the harmless
sort, we suffered daily from its effects, and it was only just before the
end of our trip that this pernicious mode of boiling it was discovered by
us.

In ascending 3000 feet from the lowlands to the highlands, or on reaching
the low valley of the Shire from the higher grounds, the change of
climate was very marked. The heat was oppressive below, the thermometer
standing at from