lie m A T 
of pure potass is 15 or 20 drops gradually In- 
creased. The form in which it is generally 
employed as a litliontriptic, is in the supersa- 
turated solution. Dose, one or two pounds 
daily. 
Soda. This is likewise used in the form of 
saturated solution, under the name of soda 
water. Dose, one or two pounds. 
Sapo a'bus. Soap is a combination of ex- 
pressed oil with potass or soda. Dose, one 
or two ounces in the course of the day. 
Calx. Lime-water is sometimes employed 
as a litliontriptic. 
ESC H AROTICS 
Are substances which destroy the texture 
of both living and dead animal matter. They 
arc employed to consume excrescences, or 
to open ulcer. Their action on the living 
system is principally, but not entirely, che- 
mical. 
The mineral acids have been employed as 
escharotics, but are not convenient, in con- 
sequence of their fluidity. 
Pdtassa, in its solid state, is a powerful 
escharotic: mixed with lime it is somewhat 
milder. 
Nitras ccrgenti. Lunar caustic. This is in 
common use. 
Murias antimonii. A powerful caustic, but 
inconvenient from its being in a fluid form. 
Sulphas cupri is often employed. 
Acstis cupri. (Verdigris.) This is milder 
than the sulphate. 
Marias h jdrargyri. Principally used in 
venereal ulcers. 
Subniiras hydrargyri. Employed with the 
same intention as the muriate. 
Oxydiun arscnici alhi. A solution of white 
arsenic is sometimes made use of as an ex- 
ternal application to cancer. 
Juniper us sabuia. Savine is principally 
applied in the form of ointment to obstinate 
ulcers. It is used in powder to consume 
warts. 
ANTHELMINTICS 
Are those medicines employed to expel 
worrris from the intestinal canal. Their ope- 
ration is supposed to be mechanical ; it may 
how ver be questioned, whether this class 
should not be a subdivision of the local sti- 
mulants, as the greater number of them seem 
to discharge worms by a stimulant rather than 
by a mechanically destructive power. 
DoUchos prurieus, cowhage, East and 
West Indies. This substance is the down 
growing on the pods of the plant. The ac- 
tion of this medicine may perhaps be princi- 
pally mechanical. 
Ferrum, iron. The filings and rust. 
Stannum, tin. This is used in the form of 
powder. Tin may perhaps operate by a me- 
chanical power. Dose, one or two drachms. 
Qlca Europaui, olive oil, oleum expression, 
South of Europe. Dose half a pound. 
Artemisia santonica, worm seed, Persia. 
Dose half a drachm. 
Spigelia marilandica, Indian pink, radix, 
North America. Dose half a drachm. 
Polypodium fiiix , , male fern, radix, 
indigenous. Dose tv : o or three drachms. 
Tanacetum vulgare, tansy, folia et flares, 
indigenous. Dose from a scruple to a 
drachm. 
Geofula inermis, cabbage bark-tree, cor- 
tex, Jamaica. Do;e thirty grains. 
} 
MAT 
Gambogia. Dose from five to twenty 
grains. 
Sitbmurias hydrargyri. Calomel is per- 
haps the most efficacious of all the anthel- 
mintics. Dose ten or twelve grains to an 
adult: 
DEMULCENTS 
Are substances employed in medicine to 
shield from acrimony; they can only act on 
the parts to which they are directly applied. 
From some circumstances, however, attend- 
ing their internal administration, it is suppos- 
ed that they are capable of bemg absorbed 
and again separated by particular secretory 
organs. This supposition does not appear to 
be entirely satisfactory. 
Mimosa nilotica, gum arabic, Africa. This 
is used to allay the irritation of the fauces in 
catarrh. It is likewise given in tenesmus, 
strangury, &c. 
Astragalus tragacdntha, tragacanlh, South 
of Europe, Asia. This has virtues Similar to 
gum arabic. It is more viscid. 
Linum usitatissimum, flax, semen, indi- 
genous. This is sometimes used in gonorrhoea, 
and catarrh. 
Althaea officinalis, marsh mallow, radix, 
indigenous. 
Malxa sylvcstris, common mallow, folia, 
indigenous. 
Glycyrrhiza glabra , liquorice, radix. South 
of Europe. These three last are all pleasant 
demulcents. 
Cycas cireinalis, sago, East Indies. This 
is a feecula from tire pith of the plant ; it is 
often given in dysentery, &c. as demulcent 
and at the same time nutritive. 
Orchis mascula, Salop, indigenous. Similar 
in virtue to sago. 
Marantu aruncNvacea, South America. 
Arrow-root is demulcent, and slightly nutri- 
tive. 
Tn/ticum hybcrnum, wheat, amylum. 
Starch is useful as an enema with opium in 
dysentery, &c. 
Cornu certi rasura, hartshorn shavings. 
Ictb/ocolla, isinglass is obtained from the 
skin of the fish. Isinglass is a demulcent in 
frequent use. 
Olea oliviv. The expressed oil principally 
used as a demulcent is obtained from the fruit 
of the olive. 
Amygdalus communis, almond oil. 01. ex- 
press. South of Europe. 
Stevum cdi. Spermaceti is obtained from 
the head of a certain species of whale. Like 
the almond oil, it is given as a demulcent in 
catarrh, &c. 
Cera, wax. This is collected from the an- 
thers of vegetables by bees, This is princi- 
pally employed in the composition of oint- 
ments and plasters. 
Of diluents and emollients the two re- 
maining classes scarcely any thing remains to 
be said. Water, strictly speaking, is the only 
diluent, and emollients are chiefly formed of 
heat combined with moisture, as in fomenta- 
tions and cataplasms, or of unctuous sub- 
stances, as lard (axungia porcina) and the va- 
rieties of expressed oils. 
MATH EM ATI CAL IN STRUM ENTS. 
See Instruments. 
MATHEMATICS, from origi- 
nally signified any discipline or learning ; but 
at present denotes that science which teaches 
or contemplates whatever is capable of being 
M A T 
numbered or measured, in so far as compu- 
table or measurable, and accordingly is sub- 
divided into arithmetic, which has number 
for its object, and geometry, which treats of 
magnitude. See Arithmetic, and Geome- 
try. 
Mathematics are commonly distinguished 
into pure and speculative, which consider 
quantity abstractedly ; and mixed, which 
treat of magnitude as subsisting in material 
bodies, and consequently are interwoven 
every where with physical considerations. 
Mixed mathematics are very comprehen- 
sive ; since to them may be referred astrono- 
my, optics, geography, hydrography, hydro- 
statics, mechanics, fortification, navigation, 
&c. See Astronomy, Optics, &c. 
Pure mathematics have one peculiar ad- 
vantage, that they occasion no disputes among 
wrangling disputants, as in other branches of" 
knowledge; and the reason is, because the 
definitions of the terms are premised, and 
every body that reads a proposition has the 
same idea of evefy part of it. Hence it is 
easy to put an end to all mathematical con- 
troversies, by shewing either that our adver- 
sary has not' stuck to his definitions* or has 
not laid down true premises ; or else that he 
has drawn false conclusions from true princi- 
ples; and in case we are able to do nei- 
ther of these, we must acknowledge the truth 
of what lie lias proved. 
It is true, that in mixed mathematics, where 
we reason mathematically upon physical sub- 
jects, we cannot give such just definitions as 
the geometricians; we must therefore rest 
content with descriptions, and they will be of 
the same use as definitions, provided we are 
consistent with ourselves, and always mean 
the same thing by those terms we have once 
explained. 
MATH IOLA, a genus of the pentandria 
monogynia * class and order. The calyx is 
entire; corolla tubular, superior, undivided, 
drupe with a globular nucleus. There is one 
species, American. 
MATRICARIA, feverfew, a genus of the 
polygamia superflua order, in the syngenesiu 
class of plants, and in the natural method 
ranking under the 49th order, composite. 
'Phe receptacle is naked ; there is no pappus; 
the calyx hemispherical and imbricated, with 
the marginal leaflets solid, and something 
sharp. There are eight species, but the only 
remarkable one is the parthenium or common 
feverfew, of which there are varieties with 
double flowers, with semi-double flowers, with 
double fist ular flowers, with a fistular disk and 
plain radius, with short-rayed flowers, with 
rayless flowers, with rayless sulphur-coloured 
heads, and with finely curled leaves. All 
these varieties flower abundantly in June, 
each flower being composed of numerous 
hermaphrodite and female florets; the former 
compose the disk, the latter the radius or 
border, and which, in the double and fistulous 
kinds, are very ornamental in gardens, but 
of a disagreeable odour; and are all succeed- 
ed by plenty of seed in autumn. This plant 
has received a most extraordinary character 
in hysteric and other affections of the nerves, 
as well as for being a carminative or warm sti- 
mulating bitter. Dr. Lewis, however, thinks 
it inferior to camomile; with which he says it 
agrees in all its sensible qualities, only being 
somewhat weaker. 
MATRICE, or Matrix, in dyeing, is ap- 
