346 
ARI 
A R I 
Argophyllum mtidurn, or the glossy argo- 
phyllum, a native of New Caledonia. Ihis 
spec ies has some affinity with the ivy. 
ARGUMENT, arguinentmn, in rhetoric 
and logic, an inference drawn from premises, 
the truth of which is indisputable ; or at least 
highly probable. 
Argument, in astronomy, denotes a 
known arch, by means of which we seek ano- 
ther one unknown. 
The argument of the moon’s latitude is her 
distance horn the node ; and the argument of 
inclination is an arch of a planet’s orbit, inter- 
cepted between the ascending node and the 
place of the planet from the sun, numbered 
according to the succession oi the signs of the 
zodiac. 
Argument of inclination, or argument of 
latitude, of any planet, is an arch ot a planet’s 
orbit, intercepted between the ascending node 
and the place of the planet from the sun, 
numbered according to the succession of the 
signs. . 
Argument, menstrual, of latitude, is the 
distance of the moon’s true place. from the 
sun's true place. — By this is found the quantity 
of the real obscuration in eclipses, or how 
many digits are darkened in any place. 
Argument, annual, pf the moon’s apogee, 
or simply, annua! argument, is the distance of 
the sun’s place from ihe place of the moon’s 
apogee ; that is, the arc of the ecliptic com- 
prised between those two places. 
ARGUS-SHELL, a species of porcelain- 
shell, beautifully variegated with spots re- 
sembling, in some measure, those in a pea- 
cock’s tail. 
ARGYTHAMNIA, in botany, a genus of 
the class and order monoecia tetandria ; the 
essential character is, male cal. four-leaved ; 
cor four-petalled ; fern. cal. five-leaved, cor. 
none, styles dicchotomous, caps, nicoceqiis, 
solitary seeds. There is one shrubby species, 
a native of Jamaica. 
ARIADNE, a beautiful statue of Parian 
marble, which was for nearly 300 years one of 
the chief ornaments of Belvidere, where it was 
placed by pope Julius II. It is now in the 
museum ot Paris. Ariadne is represented 
sleeping on the rocks of Naxos, where she 
lias been ungratefully left by Theseus. 
ARIANS, in church-history, a sect of an- 
cient Christians, who denied the three persons 
in the Holy Trinity to be of the same essence, 
and affirmed Christ to be a creature ; that he 
was inferior to the Father as to his deity ; that 
lie was neither co-eternal, nor co-equal with 
him ; also, that the Holy Ghost was not God, 
but a creature of the Son. In their doxologies, 
they ascribed glory to the Father iti the Sou, 
through the Holy Ghost. 
The term Arian, in modern times, is applied 
to all who believe in the pre-existence ot 
Christ, but who consider him as inferior and 
subordinate to the Father. 
ARI DAS, a kind of taffety, manufactured 
in tiie East Indies, from a shining thread 
which is got from certain herbs, whence they 
are stvled aridas of herbs. 
ARID ED, a fixed star of the second 
magnitude, in the extremity of the swan s 
tail. . . v 
ARIDULLAM, in natural history, a Jund 
of zarnich found in the East Indies. 
ARIES, in zoology. See Ram. 
Aries, or the Ram, in astronomy, one of 
the constellations of the northern hemisphere, 
and the first of the old twelve signs of the zo- 
diac, and marked Y in imitation ot a rain’s 
head. It gives name to a twelfth part of the 
ecliptic, which the sun enters commonly 
about the 20th of March. 1 lie stars of this 
constellation, in Ptolemy’s catalogue, are 1 8 ; in 
Tycho Brahe’s 21 ; in Helvelius’s 27 ; and in 
Flamsteed’s 66: but they are mostly very 
small, only one being ot the 2d magnitude, 
two of the 3d magnitude, and all the rest 
smaller. 
ARILLUS, in botany, the proper or exte- 
rior coat or covering oi the seed, which dry- 
ing, falls off spontaneously. All seeds have 
not this appendage 
ARISH, a Persian long measure, containing 
about 38 English inches. 
ARISTA, among botanists, a long needle- 
like beard, which stands out from the husk oi 
a grain of corn, grass, &c. 
AR1STEA, i'n botany, a genus of the tri- 
andria monogynia class and order. T he es- 
sential character is, petals six, style decimate, 
stigma funnel-shaped gaping, caps.inferior with 
many seeds. There is one species, a native of 
the Cape. 
ARISTIDA, in botany, a genus of the class 
and order triandria digynia. The essential cha- 
racter is, calyx two-valved, corolla one-yalved, 
with three terminal awns. There are six spe- 
cies, all of them natives ot the East and YY est 
Indies. 
AllISTO LOCHIA, birthwort, a genus of 
the hexandria order, belonging to the gynan- 
dria class of plants ; and in the natural method 
ranking under the 1 1th order, sarmentaeeax 
It has no calyx ; the corolla consists of one 
entire petal ; and the capsule, which is below 
the flower, has six cells. 1 he species are 
twenty-one ; but only the following merit de- 
scription. 
Aristolochia Indica, or contrayerva of 
Jamaica, is a native of that island, where its 
roots are used instead of the true contrayerva. 
It has long trailing branches, which climb 
upon the neighbouring plants, and sometimes 
rise to a considerable height. r l he flowers 
are produced in small clusters towards the 
upper part of the stalks, which are oi a dark 
purple colour. 
Aristolochia serpentaria is a native of 
Virginia and Carolina, whence the radix ser- 
pentaria, or snake-root, so much used in me- 
dicine, is brought over. The leaves grow 
close to the ground on footstalks an inch long, 
oi a singular shape, and of a dark purple co- 
lour. A round canulated capsule succeeds the 
flower. It is filled with seeds, which are ripe 
in May. When planted, in gardens, in coun- 
tries where they are natives, they increase so 
much in two years, that one can scarce grasp 
the stalk of a single one. This species is 
usually found in woods near the roots ol great 
-trees. 
The usual price of the root, when dried, 
is 6d. per lb. both in Virginia and Carolina ; 
and the negro slaves employ a great part of 
the time allowed them by their masters in 
search after it. 
Another species is the elematitis, the root 
of which has an aromatic bitterness, which is 
by no means unpleasant. 1 his root is de- 
servedly esseemed as a remedy in the ma- 
lignant fevers and epidemic diseases ot warm 
climates. It is given in substance in doses 
of from ten to thirty grains, and in infusions, 
from one to two drams. 
A R I 
ARITHMETIC is the science of numbers, 
and teaches the art of computing by them. 
At what time this science was introduced into 
the world cannot be easily determined. History 
fixes neither the author nor the time. The Greeks 
verv early made use of the letters of the alpha- 
bet "to represent their numbers. The 24 letters, 
taken according to their order, at first denoted 
the numbers 1, 2, 3, 4, 5, 7, 8 , 9, 10, 20, 30, 40, 
50, 60, 70, 80, 100, 200, 300, 400, 500, 600, 700, 
and 800 ; to which they added the three follow- 
ing* r, k "), to represent 6 , 90, and 900. 
The Romans followed a like method ; and be- 
sides characters for each rank of classes, intro- ; 
dneed others for five, fifty, and five hundred. ; 
Their method is still used for distinguishing the ; 
chapters of books, and some other purposes, j 
Their numeral letters and values are the fol- 
lowing : 
I V X L C D 
One, five, ten, fifty, one hundred, five hundred;, 
M 
one thousand. 
Any number may be represented by repeat- 
ing and combining these according to the follow- 
ing rules. 
(1) When the same letter is repeated twice, or 
oftener, its value is represented as often. Thus 
II signifies two ; XXX thirty, CC two hundred, j 
(2) When a numeral letter is placed after one of 
greater value, their values are added : thus XI 
signifies eleven, LXV sixty-five, MDCXXVIII 
one thousand six hundred and twenty-eight. 
(3) When a numeral letter is placed before one 
of greater value, the value of the less is taken j 
from that of the greater : thus IV signifies four, 
XL forty, XC ninety, CD four hundred. 
Sometimes I 3 is used instead of D for 500, 
and the value is increased ten times by annex- 
ing 3 to the right hand. 
Thus, I 3 signifies 500 
I 33 - 5000 
I 333 _ 50000 
Also, C 13 is used for 1000 
CC 133 for 10000 
CCCI 333 for 100000 
Sometimes thousands are represented by 
drawing a line over the top of^the numeral, V 
being used for five thousand, L for fifty thou- 
sand, CCT two hundred thousand. 
About the year of Christ 200, a new kind of 
arithmetic, called sexagesimal, was invented 
probably by Ptolemy, to remedy the difficul- 
ties of the common method, especially with re- 
gard to fractions. Every unit was supposed to 
be divided into 60 parts, and each of these into 
60 others, and so on. Thus from one to 59 were 
marked in the common way : then 60 was called 
a sexagesima prima, or first sexagesimal integer, 
and had one single dash over it ; so . 60 was ex- 
pressed thus V ; and so on to 59 times 60, or 
3540, which was thus expressed LIX' He now 
proceeded to 60 times 60, which he cahed z 
sexagesima secunda, and was thus expressed I • 
In like manner, twice 60 times 60, or 7200, was 
expressed by II // ; and so on till he came to 60 
times 3600, which was a third sexagesimal, and 
expressed thus V" . If any number less than 60 
was joined with these sexagesimals, it was added 
in its proper characters without any dash : thus 
I'XV represented 60 and 15, or 75 ; EV XXV is 
four times 60 and 25, or 265; XAEAV is t ;ti 
times 9000, twice 60 and 15, or 36, 135, &c. 
Sexagesimal fractions were marked by putting 
the dash at the foot, or on the left-hand of the: 
letter : thus I /f or 'I; denoted \ /p or A, 
&c. So nearly did the inventor of this method 
approach the Arabic, or common mode of not a- 
‘ tion ; instead of sexagesimal progression, it was 
