1846 .] 
THE NATIONAL INSTITUTE. 
537 
articles at present in the Portuguese possessions on this coast, is at Sofala. The 
chief commodities given in exchange for ivory and gold dust are large brass rings, 
and coarse colored calicoes, blue and red colors being preferred. The rings are 
made of round bar brass of an inch diameter, and the ring thus made being six or 
eight inches diameter. They are not welded, and worn around the neck. Smaller 
ones are worn on the ankles and wrists. Formerly there was, on an average, ten 
thousand slaves exported from this place annually, and the slave trade is still 
probably carried on to a small extent, but all commerce appears declining, and at 
present not more than two hundred Europeans remain. During the spring 
months of the northern hemisphere, this place is said to be very unhealthy, and is 
probably caused by a large extent of ground which is left uncovered by water when 
the tide ebbs, and from which a very disagreeable smell emanates. 
November , 1844.—The immediate vicinity of Bembetooka bay presents compara¬ 
tively little to the botanist for a tropical country, and although the ground is 
parched in the same manner as the neighborhood of St. Augustin bay, yet it has 
a very different aspect; for here near the village may be seen the mango, cocoa-nut, 
banana, and orange tree, although, from appearance, the two latter have been but 
lately introduced. The opposite side of the bay has apparently a much better 
soil, and denser vegetation, but is inhabited by the Sackalavas, who are at present 
hostile with the BLoovas, so that in consequence of this circumstance and the dis¬ 
tance, I found it impracticable to visit it. I regretted this the more, as the silk 
worm is reared there, and is said to be very different from the European varieties, 
being much larger and covered with hair, and are said to be fed on a kind of pea. 
I saw none of the silk fabric produced from this worm, and consequently am unable 
to compare it with the kind produced in the United States; but I think the subject 
merits attention, as there can be no doubt but that in a few years silk will form 
one of our staple productions, for even in Pennsylvania, at present, nothing repays 
the careful cultivator so well in proportion to the extent of ground tilled as this 
branch of industry, and much more so will it be in the southern States when pro¬ 
perly understood, where the climate is much more congenial. 
The Datura stramonium is seen growing in the streets of Bembetooka, and no 
doubt has been introduced by the Arabs, who have had considerable trade with this 
port. 
The Euphorbia splendida is cultivated in the village for hedges, and although a 
large shrub, it is not well adapted for this purpose, having no thorns or asperities. 
The buds on this shrub were just beginning to burst, in consequence of a slight 
shower of rain which had fallen, and denoted the commencement of the rainy 
season. 
A tree found abundantly on the small stony hills in the vicinity of the town, re¬ 
sembling an ash in habit, but belonging to the Leguminosa, yields a gum in pro¬ 
perties identical with gum sulo. I obtained seed of this tree in a good state, and 
I think it may bear the climate of our southern country. 
In the small groves which are situated at the base of some of the small hills, will 
frequently be found the tangena, (Tanghinia venemflua,) a pentandrous shrub, 
having a white flower. The corolla is tubular, five cleft, with the divisions some¬ 
what reflexed, the leaves are lance ob-ovate, accuminate and slightly revolute on 
the margin. Petiole short, fruit adrupe. 
The fruit of this plant appears to be a violent emetic, and is frequently used by 
the officers of justice in this kingdom, as an ordeal to ascertain the guilt or inno¬ 
cence of suspected criminals, where the evidence is not clear. The criminal 
is made to swallow three pieces of skin of a black fowl, when a copious decoction 
of the fruit of this plant is given, which produces violent emesis, and if the three 
pieces of skin are ejected, the prisoner is declared innocent; but should any remain, 
he suffers the penalty of the crime of which he is accused, and which frequently, 
for the most trivial offence, is death. It is very probable this plant would possess 
medical properties if it were properly investigated. 
I obtained here two varieties of indigo seed, the coloring matter of which the 
natives use in dyeing their cloth, and a piece which has been the labor of three 
weeks they eagerly sell for one dollar. 
The Hymenora verrucosa grows only in the interior, and produces gum copal, 
©f which there are two kinds brought to market at this port, one kind, called “Jack- 
