054 
REA 
ft E C 
REA 
Caloric not only possesses the velocity of 
l'gnlj hilt agrees with it also in another pro- 
perty no less peculiar. Its particles are 
never tound cohering together in masses; 
and whenever tluey are forcibly accumulated, 
they jly off in ail directions, and separate 
~h' om each other with inconceivable rapidity. 
I ms property necessarily supposes the exist- 
ence of a mutual repulsion between the par- 
ticles of caloric. 
1 hits i< appears that caloric and light re- 
»emb’e each other in a great number of pro- 
perties. Both are emitted from the sun in 
rays, with the velocity of 200,000 miles in a 
second; both of them are retracted by trans- 
parent bodies, and reflected bv polished sur- 
faces ; both of them consist of particles which 
mutually repel each other, and which pro- 
duce no sensible effect upon the weight of 
other bodies. They differ, however, in this 
particular; light produces in us the sensation 
of vision ; caloric, on the contrary, the sen- 
sation of heat. 
Upon the whole, we are authorized by the 
above statement of facts, to conclude, that 
the solar light is composed of three distinct 
substances, in some measure separable by the 
prism on account of the difference of their 
refrangibllity. The calorific rays are the least 
refrangible, the deoxidizing rays are most re- 
frangible, and the colorific rays possess a 
mean degree of refrangibility. " Hence the 
rays in the middle of the spectrum have the 
greatest illuminating power, those beyond 
the red end the greatest heating power, and 
those beyond the violet end the greatest de- 
oxidizing power: and the heating power on 
the one hand, and the deoxidizing power on 
the other, gradually increase as we approach 
that end of the spectrum where the maximum 
of each is concentrated. These different bo- 
dies resemble each other in so many particu- 
lars, that the same reasoning respecting re- 
frangibility, retlexibility, &c may be applied 
to all; but they produce 'different effects 
upon those bodies on which they act. Little 
progress has yet been made in the investiga- 
tion of these effects ; but we may look for- 
ward to this subject as likely to correct many 
vague and unmeaning opinions which are at 
present in repute among philosophers. 
RAZOR-BILL. See Alka. 
REACH, in the sea language, signifies the 
distance between any two points of land, 
Jytng nearly in a right line. 
RE- ACTION, in physiology, the resist- 
ance made by all bodies to the action or im- 
pulse of others, that endeavour to change 
its state whether of motion or rest. See 
Motion, 
REALGAR, a mineral found in Sicily and 
various part's of Germany. ‘ If is ‘ either mas- 
sive or crystallized. The primitive form of 
the crystal is an octahedron with scalene.tri- 
angies, and it commonly appears in 4, 6, 8, 
30, or 12 sided prisms, terminated by four- 
sided summits. Colour red. Streak yellow- 
ish-red. Specific gravity 3.338. It is elec- 
tric per se, and becomes negatively electric 
by friction. Before the blowpipe it melts 
easily, burns with a blue flame, and soon eva- 
porates. It is also the old name for a sul- 
phuret of arsenic, found native in different 
parts of Europe. It has a scarlet colour, and 
is often crystallized in transparent prisms. \ 
Its specific gravity is 3.2. it is composed of j 
I 50 parts of arsenic, and 20 of sulphur, and it 
is sometimes used as a part. 
_ REAR, a term frequently used in compo- 
sition, to denote something behind, or back- 
wards, in respect of another, in opposition to 
van: thus, in a military sense, it is used for 
j the hind part of an army, in opposition to the 
1 front, for the rear -guard, rear half- files, 
rear-line, rear-rank, and rear-admiral. 
RL-AT1 ACHMENT, a second attach- 
ment of him that was formerly attached and 
dismissed the court without day, as by the 
not coming ot the justices, or some such ca- 
sualty. 
REAUMUR1A, a genus of the class and 
order polyandria pentagynia. The calyx is 
six-leaved ; petals five ; caps, one-celled, five- 
valved, manv-seeded. There is one species, 
an annual ot Egypt. 
REBATE, or Rebatement, in com- 
merce, a term much used at Amsterdam, for 
an abatement in the price of several commo- 
dities, when the buyer, instead of taking 
time, advances ready money. 
R EBELLION, taking up arms traitorously 
against the king, be it by natural subjects, or 
by others once subdued. See Riot. 
REBUTTER, is the answer of the defend- 
ant to the plaintiff’s sur-rejoinder. 
RECAPITULATION, in oratory, &.c. is 
a summary, or a concise and transient enu- 
meration, of the principal tilings insisted on 
in the preceding discourse, whereby the 
force of the whole is collected into one view. 
RECAPTION. Where one has deprived 
another of his property, the owner may law- 
fully claim and retake it wherever he hap- 
pens to find it, so that it shall be not in a 
riotous manner, or attended with any breach 
of the peace. 
RECEIPTS, are acknowledgments in 
writing of having received a sum ot money or 
other value. A receipt is either a voucher 
tor an obligation discharged or one incurred 
Receipts for money above 40.?. must be on 
stamps: but on the back of a bill of exchange 
or promissory note which is already stamp- 
ed, is good without a farther duty. Writing' 
a receipt on a stamp of greater value than the 
law requires, incurs no penalty, and the re- 
ceipt is good ; but if on a stamp of a lower 
value, or on unstamped paper, then a re- 
ceipt is no discharge, and incurs a penalty. 
See Stamp. 
RECEIVER, in pneumatics, a glass ves- 
sel for containing the thing on which an 
experiment in the air-pump is to be made. 
See Pneumatics. 
Receiver, in chemistry, a vessel of earth, 
glass, &c. for receiving any distilled liquor. 
Receiver. Receiving stolen goods, know- 
ing themto ( b£ s£olpn x a, high, njisderpea- 
nour at the common law ; and by several sta- 
tutes is made felony and transportation ; and 
in some particular instances, felony without 
benefit of clergy. 
Receiver also signifies an officer, of 
which there are several kinds, denominated 
from the particular matters they receive, the 
places where, or the persons from whom, &c. 
1 . Receiver of the fines is an officer appoint- 
ed to receive the money of such persons as 
compound with the king, upon original writs 
sued out of chancery. 2. Receiver-general 
ol the duchy of Lancaster is an officer be- 
longing to the duchy-court, who collects all 
the revenues, fines, forfeitures, and asses*- 
4 
merits, within that duchy, 3. Receiver-ge4 
ueral of the public revenue, is an officer ap- 
pointed in every county, to receive the taxes 
granted by parliament, and remit the money 
to the treasury. * 
RECIPE, in medicine, a prescription or 
remedy, to be taken by a patient; so called 
because always beginning with the word re- 
cipe, i. e. take ; which is generally denoted' 
by the abbreviature j^. 
RECIPIANGEE, or Recipient ancle, 
a mathematical instrument, serving to mea- 
sure re-enlering and saliant angles, especially 
in fortification. 
It usually consists of two arms, or rulers 
AC, and BC (Plate Miscel. fig. 197) riveted 
together at C, and capable of being opened 
and closed, like a sector. To take an angle 
with it, they lay the centre of a protractor over 
the joint C, and apply its diameter to one of 
the rulers; then the degrees cut by the edge 
of the other ruler, shew the quantity of the 
angle. 
There are other forms of this instrument : 
that represented tig. 198, has a graduated 
circle, by which the angles may be readily 
measured by its index; and fig. 399, f s 
another kind composed of four equal rulers 
of brass, riveted together by their ends, so as 
to form a parallelogram ; and on one of the 
rulers is fixed a graduated semicircle, which 
measures the opposite angle of the parallelo- 
gram, by means of one of the rulers produced, 
so as to serve instead of an index. 
RECIPROCAL terms, among logicians, 
1 are those which have the same signification ; 
and consequently are convertible, or may be 
used for each other. 
Reciprocal figures, in geometry, those 
which have the antecedents and consequents 
of the same ratio, in both figures. Thus, 
(Plate Miscel. fig. 200,) A:B::C:D; or 
12:4:: 9; 3; that is, as much as the side 
A, in the first rectangle, is longer than B, so 
much deeper is the side C, in the second rect- 
angle, than the side D in the first ; and, con- 
sequently, the greater length of the one is 
compensated by the greater breadth or depth 
ot the other , tor as the side A is ^ longer' 
than C, so B is I longer than D, and The 
rectangles of course equal ; that is, A -f- D 
= }] X C, °r 12 x 3 = 4X 9 = 36. 
1 his is the foundation of that capital tlieo- 
u ni, viz. that the rectangle of the extremes is 
always equal to that of the means ; and, con- 
sequently, the reason of the rule of three. 
Hence it follows, that if any two triangles, ] 
parallelograms, prisms, parallelepipeds, py- 
ramids, cones, or cylinders, have their bases 
and altitudes reciprocally proportional, those 1 
two figures or solids are equal to each other; 
a.n'J, vice versa, if they are equal, then their 
bases and altitudes are reciprocally propor- 
tional. See Triangle, Parallelogram, 
&c. 
j\^ciprocal proportion, in arithmetic 
is when, in four numbers, the- fourth is less 
than the second, by so much as the third is - 
greater than the first ; and vice versa. 
This is the foundation of the inverse, or in- : 
direct, rule of three : thus, 4: 10 : : 8 : 5. 
It is applied also to quantities which, being I 
multiplied together, produce unity. Thus -i_ 
and, .v, y and are reciprocal quantities, b«* 
