' RES 
it were found by Pilatre not to give a green 
colour to vegetable blues. The gases be- 
longing to the second class may be drawn 
into the lungs, and thrown out again with- 
out any opposition from the respiratory 
organs ; of course the animal is capable of 
respiring them. They may be divided into 
four subordinate classes; — 1. The first set 
of gases occasion death immediately, but 
produce no visible change in the blood. 
They occasion the animal’s death merely by 
depriving him of air, in the same way as he 
would be suffocated by being kept under 
water. The only gases which belong to 
this class are hydrogen and azotic. 2. The 
second set of gases occasion death imme- 
diately ; but at tlie same time they produce 
certain changes in the blood, and therefore 
kill, not merely by depriving the animal of 
air, but by certain specific properties. The 
gases belonging to this class are carbureted 
hydrogen, sulphureted hydrogen, carbonic 
oxide, and perhaps also nitrous gas. 3. The 
third set of gases may be breathed for some 
time without destroying the animal ; but 
death ensues at last, provided their action be 
long enough continued. To this class belong 
the nitrous oxide and oxygen gas. 4. The 
fourth set may be breathed any length of 
time without injuring the animal. Air is the 
only gaseous body belonging to this class. 
See Physiology, and Thomson’s Chemistry, 
KESPONDEAS ouster, is to answer 
over in an action to the merits of the cause. 
As if a demurrer is joined upon a plea to 
the jurisdiction, person, or writ, and it be 
adjudged against the defendant, it is a res- 
jpondeas ouster. 
REST, the continuance of a body in the 
same place, or its continual application or 
contiguity to the same parts of the ambient 
or contiguous bodies ; and therefore is op- 
posed to motion. Sir Isaac Newton defines 
true or absolute rest to be the continuance 
of a body in the same part of absolute 
space j and relative rest to be tlie conti- 
nuance of a body in the same part of rela- 
tive space. Thus, in a ship under sail, rela- 
tive rest is the continuance of a body in the 
same part of the ship; but absolute is its con- 
tinuance in the same part of universal 
space, in which the ship itself is contained, 
It is one of the laws of nature, that mat- 
ter is indifferent to motion or rest, as has 
been shown under the article Inertia. 
Rest, in poetry, is a short pause of the 
voice in reading, being the same with the 
paesura, which, in Alexandrian verses, falls 
on the sixth syllable ; but in verses of ten 
pr eleven syllables, on the fourth. 
RET 
RESTIO, in botany, a genus of the Dio- 
ecia Triandria class and order. Natural or- 
der of Calamariae. Essential character : 
calyx three-leaved, two of the leaflets boat- 
shaped ; corolla three-leaved, leaflets lanceo- 
late, one wider : female, germ three-sided ; 
style one, seldom two or three ; stigmas 
one, two, three, feathered. There are 
twenty-eight species. These plants are all 
natives of the Cape of Good Hope, where 
some of them are used for making ropes, 
for brooms, or for thatching. 
RESULTING «se, in law, is when an use 
limited by a deed expires, or cannot vest, 
it returns back to him who raised it. See 
Uses. 
RETAINER of debts, an executor, 
among debts of equal degree, may pay him- 
self first, by retaining in his hands, the 
amount of his debt. 
RETARDATION, in physics, the act 
of diminishing the velocity of a moving bo- 
dy. If bodies of equal bulk, but of differ- 
ent densities, be moved through the same 
resisting medium, with equal velocity, thq 
medium will act equally on each, so that 
they will have equal resistances, but their 
motions will be unequally retarded, in pro- 
portion to their densities. Retarded mo- 
tion from gravity is peculiar to bodies pro- 
jected upwards, and this in the same man- 
ner as a falling body is accelerated ; only 
in the latter, the force of gravity acts in the 
same direction with the motion of the bo-^ 
dy ; and in the former in an opposite di- 
rection. As it is the same force which 
augments the motion in the falling, and di- 
minishes it in the rising body, a body will 
rise till it has lost all its motion ; which it 
does in the same time wherein a body fall- 
ing would have acquired a velocity equal to 
that wherewith the body was projected up- 
wards. 
RETE mucosum, in animal economy, is 
the mucous substance, situated between the 
cutis vera and epidermis, its composition 
cannot be determined with precision, be- 
cause its quantity is too small to admit of 
examination. It is known, that the black 
colour of negroes depends upon a black 
pigment, situated in this substance. Oxy- 
muiiatic acid deprives it of its black co- 
lour, and renders it yellow. A negro, by 
keeping his foot for some time in water im- 
pregnated with that acid, deprived it of its 
colour, and rendered it nearly white ; but 
in a few days the black colour returned 
again with its former intensity. This expe- 
riment was first made by Dr. Beddoes, or| 
the fingers of a negro. 
