MIRACLES. 
pretences to inspiration and miracles, made 
by false prophets, in support of error ami 
idolatry, as tlie sole elFects of human craft 
and iinposUne. And, therefore, since an- 
gels, whether good or evil, the spirits ot de- 
parted men, the lieathen deitie.s, magicians, 
and false prophets, are the only agents 
who have ever been conceived as capable 
of working miracles, eitlier in opposition to 
God, or without an immediate commission 
from him ; and the Scripture denies to all 
these, the power of performing any niira- 
eles; it does in effect deny, that any single 
miracle has ever been performed without 
the immediate interposition of God. It is 
likewise alleged, that the Scriptures repre- 
sent the one true God as the sole Creator 
and Sovereign of llie world, which lie go- 
verns by fixed and invariable laws; that to 
him they appropriate all miracles, and that 
they urge them as demonstrations of his di- 
vinity and sole dominion over nature, in op- 
position to the claims of all other superior 
beings. Tlie Scriptures also uniformly re- 
present all miracles as being, in themselves, 
an absolute demonstration of the mission 
and doctrine of the prophets, at whose im 
stance they are performed ; and never di- 
rect us to regard their doctrines as a test ot 
tlie miracles being the effect of divine inter- 
position. Accordingly, the miracles of 
Ciirist, in particular, were a demonstration 
(not a partial and conditional, but a com- 
plete and absolute demonstration) of his 
mission from God : and they were further 
desiirned to evince his peculiar character as 
the Messiah, or anointed ; i. c. his regal 
commission and power, or his riglit by di- 
vine designation to dominion and judicature 
over mankind. And it may be observed, 
witli respect to all the miracles of the New 
Testament, that their divinity, considered 
in themselves, is always either expressly as- 
serted, or manifestly implied ; and they are 
accordingly urged as a decisive and abso- 
lute proof of the divinity of tlie doctrine 
and testimony of tlieir pei formers, witliont 
ever taking into consideration the nature 
of the doctrine, or of the testimony to be 
confirmed. It is also shown, that the Scrip- 
tures have not recorded any instances of 
real miracles performed by the Devil ; in 
answer to the objections drawn from tiie 
case of tlie magicians in Egypt, from tiie 
appearance of Samuel, after his decease, to 
Saul, which was either tlie work of human 
imposture, or a divine miracle, and from 
oiir Saviour’s temptation in the wilderness, 
which the writer, to whom we now refer, 
considers as a divine vision. 
Miracles, considered as the peculiar 
works of God, afford a divine testimony to 
the person on whose account tliey are 
wrought, and to that doctrine or mtssage, 
which he delivers in the name of God. And 
this proof from miracles, of the divine com- 
mission and doctrine of a projihet, is in 
itself decisive and absolute. It is also the 
most natural and agreeable to the common 
sense of mankind in all ages. It is the 
most easy and compendious proof of a new 
revelation. Miracles are further a very 
powerful method of conviction, making a 
strong impression upon tiie heart, at tlie 
same time tliat they carry light to the im- 
dei'standing. Nor is the necessity of mira- 
cits less evident than their propriety and 
advantage, in attesting a divine commission 
and propagating a new revelation. They 
also serve to revive and confirm ilie princi- 
ples of natural religion, and to recover men 
from those two opposite extremes of atheism 
and idolatry. Finally, the evidence of mi- 
racles, whether of power or knowledge, is 
the fittest to accompany a standing revela- 
tion ; because it is not confined to one age 
or nation, but may be extended over the 
whole globe, and conveyed, to the most dis- 
tant generations. 
MIRROUR, in catoptrics, any polished 
body impervious to the rays of liglit, and 
which reflects them equally. 
Mirrours were anciently made of metal ; 
but, at present, they are generally smooth 
plates of glass, tinned or quicksilvered on the 
back part, ami called looking-glasses. The 
doctrine of mirrours depends wholly on that 
fumiamenlal law, that the angle of reflec- 
tion is always equal to the angle of inci- 
dence. See Optics. 
Parallel rays falling directly on a plane 
speculum are reflected back upon them- 
selves; if they fall obliquely, they are re- 
flected in the same angle, and parallel as 
they fell. Hence there is no such thing, 
properly speaking, as a focus belonging to 
a plane speculum, neither real nor virtual. 
Tiie focus of parallel rays is called the solar 
focus ; because in that the image of the sun 
is formed, and of all objects very remote. 
But the focus of any object situated near 
the mirrour, will have its distance from the 
vertex more or less than half the radius; 
die rule in all cases being as follows : “ Mul- 
tiply the distance of the object into the ra- 
diu.s of the mirrour, and divide the product 
by the sum of the radius, and twice tlie dis- 
tance of the object ; the quotient will be 
the focal distance of a copve.x mirrour.” 
Again, for a concave niirrGiir, the saw* 
