TOM 
tab five, the lowest twice as big, obcor- 
date : style none. There is but one spe- 
cies, piz. T. balsamuin, balsam of tolu tree. 
It is a native of Spanish America, in the 
province of Tolu, near Carthagena ; it is a 
tree of a* considerable size, the bark is 
thick, rough, and of a brown colour, the 
branches spread wide on every side; leaves 
alternate, oblong, four inches long, and two 
broad in the middle, rounded at the base, 
acuminate at the end, smooth, of a light 
green colour, on very short foot stalks ; the 
flowers are produced in small axillary race- 
mes, or bunches, each on a slender pedicel ; 
the corolla has four narrow petals of a yellow 
colour, a little longer than the calyx, and a 
fifth, the claw of which is of the same 
length as the, other petals, and the top 
ovate cordate; stamens within the tube, 
and terminated by oblong erect sulphur- 
coloured anthers ; fruit roundish, the size of 
a large pea, divided into four cells, each 
containing one oblong ovate seed. The 
balsam of Tolu, which is brought to Europe 
' in little gourd shells, is obtained by mak- 
ing incisions in the bark of the tree ; it is 
collected in spoons, which are made of 
black wax, and from them it is poured into 
proper vessels ; it is of a reddish yellow 
colour, transparent, in consistence thick, 
and tenacious ; by age it grows hard and 
brittle, so that it may be rubbed into a 
powder between the finger and thumb ; its 
smell is extremely fragrant; its taste is 
warm and sweetish ; thrown into the fire it 
immediately liquifies, takes flame, and dis- 
perses its azreeable odour. 
TOMENTUM, in botany, short-wool, a 
species of hoary or downy pubescence, 
which covers the surface of many plants, 
particularly those in the neighbourhood of 
the sea, and such as in their native soil 
are exposed to the ravages of bleak and 
violent winds. The substance in question 
consists of a number of small hairs, that are 
so closely interwoven as scarcely to be dis- 
tinguished by the naked eye, the white 
appearance arising from their aggregation 
and compact texture. 
TOMEX, in botany, a genus of the 
Dodecandria Monogynia class and order. 
Essential character : involucre four or five- 
leaved ; calyx none ; corolla five-petalled ; 
nectary scales five, between the lower sta- 
mens; berry one-seeded. There arc three 
species, ’among which we shall notice the 
T. sebifera, glutinous tomex, or tallow- 
tree ; it grows to a considerable size, with 
spreading branches; leaves ovate, oblong, 
VOL. VI. 
TON, 
quite intire, smooth, alternate, petioled ; 
peduncles lateral, and subterminating, two 
or three-flowered; berries small, smooth, 
and blackish. Native of China and Cochin- 
China. The wood, which is light, and of a 
pale colour, is used for rafters, studs, &c. 
in btiilding ; the leaves and twigs abound in 
a viscid juice, and being bruised and mace- 
rated in water, render it glutinous, for this 
reason the natives work tip their plaster 
with it, to render it more tenacious, and 
also that it may last the longer ; a great 
quantity of a thick w’hite oil is extracted 
from the berries, of which common candles 
are made, resembling spermaceti or wax 
candles, but having an unpleasant smell. 
TOMPION, in naval aflairs, a circular 
piece of wood used to stop the mouth of a 
cannon. At sea the tompions are carefully 
encircled with tallow or putty, to prevent 
the penetration of the water into the bore, 
whereby tire powder contained in the 
chamber might be rendered unfit for ser- 
vice. 
TONNAGE, in military and naval af- 
fairs, a custom or impost dogjiur merchan- 
dize, brought or carried in tons, from or to 
other nations, after a certain rate, in every 
ton. The method of finding the tonnage 
of aoy ship is by the following rule : Multi- 
ply the length of the keel by the breadth of 
the beam, and that product by half the 
breadth of the beam, and divide the last 
product by 94, and the quotient will be 
the tonnage. Ex. Suppose the ship’s keel 
72 feet, breadth of the beam 24 feet, then 
72 X 24 ^ — 220.6. The tonnage of 
94 
goods is sometimes taken by weight, and 
sometimes by measurement. The method 
which yields the most is allowed to' a ves- 
sel. In weight twenty hundred make one 
ton, but by measurement forty cubic feet 
are equal to one ton. 
TONSELLA, in botany, a genus of the 
Triandria Monogynia class and order. Es- 
sential character: calyx five-parted ; pe- 
tals five; nectary pitcher-shaped; berry 
one-celled, four-seeded. There are two 
species, mz. T. scandens, climbing tonsella ; 
and T. afrieana, African tonsella,- both na 
lives of Guinea. 
TONSILS, in anatomy, two remarkable 
glands, situated one on each side of the 
mouth, near the uvula, and commonly called 
almonds of the ears, from their resetnbling 
almonds in figure. Their nse. is to secrete a 
mucous humour for lubricating the pas- 
sages : this they discharge by several irrae 
E e. 
