OPI 
i ers as coarfe and vulgar in mind and manner. In 
f: ie by no means merited fuch an unfavourable report ; 
he was plain and unaffected, poke his mind freely ; was 
by no means adapte ¥ 
he was not aaa offenfive, and condemned warmly thofe 
who were 
fed a tenacious memory, and readily quoted in 
pone acon the authors he had read, particularly a poets, 
anion when he found 
The cE which he delivered at the Royal Academy 
are publifhed to the-world, it is therefore not neceffary to en- 
ter upon their merits; but it w ill be juftice to their author, 
earheftly to recommend the perufal of them to all who with 
to underftand the principles of the art on which they treat. 
Unhappily the courfe was incomplete,- as he only gave four 
leGures of the fix prefcribed to each profeffor, The wo rld 
were deprived of all 
atl his death, which occurred, after a lingering inet in April 
e was honoured b n St 
ecieael near the grave of 
neral was moft refpectably attended by 
bers of the castles 8 and many of ne apply and 
gentry of the co 
oe a O, in Naiural Hiftory, a {pecies of Phalangium ; 
whic 
OPIMATORES, among the Romans, aulitar ry m 
who had the dire@tion and management of the oa done 
and were to take care that the army wanted nothing. 
OPINION, Opinio, denotes a probable belief ; or a 
te a9 uncertain judgment of the mind. 
pinion is better defined the affent of the mind to propo- 
fitions a ‘aaa true at rit fight ; nor deduced, by ne- 
saul confequence, from others that are fo; but ‘foch as 
carry the face of truth 
The fchools define opinion, afen/fus intelleCtus cum formidine 
de oppofito 5 ‘an affent of the un — nee: with fome fear or 
diftrudt of the contrary bein 
According to logicians, deeoitates begets {cience, or 
knowledge ; and probable arguments beget opinion 
Wherever the mind’s acquiefcence in a ea propofed to 
it is accompanied with any doubt, this 1s what we.call an 
opinion, and it is the refult of obfcure and indeterminate per- 
That the planets revolve about the fun is a branch 
ception. 
of knowledge: that they are inhabited by beings fimilar to 
men is only an opinion. ence, knowledge is faid to be cer- 
tain, opinion uncertain. *. Of 0 » fome are probable 
falfe anda r the evidence 
of whofe falfehood preponderates over that of its truth. 
ato“‘makes opinion a med etween knowledge and 
ignorance; clearer and more exprefs ne es yet more 
obfcure and pala than know 
OP STHODOM! crab among the Athenians, 
the public treafury, fo calle ed from its being fituated on the 
backfide of Minerva’s temple. Here, befides other public 
money, a thoufand talents were laid in ftore, againft any 
very urgent occafion; but if any man expended them upon 
a trivial account, he was to be put to death. -Alfo the names 
that were indebted to the commonwealth were 
entered in a regifter in this place. The tutelar gods-of this 
OPI 
treafury, were Jupiter Zeine, or the Saviour, and Plutus, the 
god of riches, whom they reprefented with wings, and 
placed next to the ftatue of 5 upiter the Saviour ; which was 
unufual in other places. ; 
OPISTHOGRAPHUM, oma QorypaPov, among the An- 
cients, a wafte-book, or fchedule,.on which were writ extem- 
ftwardi that wanted to he vevifed and corrected af- 
war 
ot ry 
aad 
bd 
word is euro of onicde, #¢. afterwards, or 
on the Lach de, and ypxdw, f write ; becaufe it was writ over 
again on the backfide of every page, which was left blank 
for that purpofe. 
OPISTHOTONOS, from orioGe, - backward, and sows, 
from tev, to extend, in Surgery, that {pecies of tetanus, in 
which the head pa trunk are drawn backward by the muf- 
cles. See Ter 
OPIUM, in Cen sfiry id Medicine. Several vegetables 
furnifh a milky flu ere when iocentanie a pro see 
pileea ») aa alio, in final quantity, from the ihe feces 
of the poppy.’ 
white poppy is aabeetias to re extent in Turkey 
for the purpofe ef affording op r the flowering of 
the plant, when the capfule pais ts feed has arrived 
at its full growth, flight longitudinal.incifions are made in 
the capfules towards the evening. 
eee val the name of ial Indian opium, This is poster 
ofter than the Turkey, of a darker colour, lefs bitter, and 
more difagreeable to the tafte, and has a difagreeable em- 
pyreumatic fmell. 
n empyreumatic {mell, it i 
Its tafte fhould be bitter but not {weet 
/pium foftens with heat fo as to adhere to the fingers, 
ut it does not fufe. en it is reduced to powder, and 
ia into a es with alcohol or water, and an extra quan- 
tity of fluid added, the greateft part of it will diffolve-by 
boiling it for fome time, a great part of which is depofited on 
ing. e have already given the means of feparating a 
peculis fubftance from opium, under the article Narcotic 
s bad. 
aw water, therefore, appear to aioe the 
principal nee _ opium, but the alcoholic folution is generally 
— 
‘ous *Tolution i 1s rather lefs coloured than that with 
alfo lefs fmell and tafte e. It affords a 
Principle, i 
three Seances namely, the narcotic principle, to which it owes 
its property -of leflening the tenfibility of the fyftem ; of 
a relin, to which it owes its ftmulating virtues, and its Side 
inflammability ; and the oxygenated extra, to w 
e 
