Encyclopaedia Britannica, 11th Edition | Page 7

to have been taken
prisoner; but the poem is very obscure and is differently interpreted. It

was translated and edited by W.F. Skene in his Four Ancient Books of
Wales (1866), and Stephens' version was published by the
Cymmrodorion Society in 1888. See CELT: Literature (Welsh).

ANEURYSM, or ANEURISM (from Gr. [Greek: aneurisma], a
dilatation), a cavity or sac which communicates with the interior of an
artery and contains blood. The walls of the cavity are formed either of
the dilated artery or of the tissues around that vessel. The dilatation of
the artery is due to a local weakness, the result of disease or injury. The
commonest cause is chronic inflammation of the inner coats of the
artery. The breaking of a bottle or glass in the hand is apt to cut through
the outermost coat of the artery at the wrist (radial) and thus to cause a
local weakening of the tube which is gradually followed by dilatation.
Also when an artery is wounded and the wound in the skin and
superficial structures heals, the blood may escape in to the tissues,
displacing them, and by its pressure causing them to condense and form
the sac-wall. The coats of an artery, when diseased, may be torn by a
severe strain, the blood escaping into the condensed tissues which thus
form the aneurysmal sac.
The division, of aneurysms into two classes, true and _false_, is
unsatisfactory. On the face of it, an aneurysm which is false is not an
aneurysm, any more than a false bank-note is legal tender. A better
classification is into spontaneous and traumatic. The man who has
chronic inflammation of a large artery, the result, for instance, of gout,
arduous, straining work, or kidney-disease, and whose artery yields
under cardiac pressure, has a spontaneous aneurysm; the barman or
window-cleaner who has cut his radial artery, the soldier whose
brachial or femoral artery has been bruised by a rifle bullet or grazed by
a bayonet, and the boy whose naked foot is pierced by a sharp nail, are
apt to be the subjects of traumatic aneurysm. In those aneurysms which
are a saccular bulging on one side of the artery the blood may be
induced to coagulate, or may of itself deposit layer upon layer of pale
clot, until the sac is obliterated. This laminar coagulation by constant
additions gradually fills the aneurysmal cavity and the pulsation in the
sac then ceases; contraction of the sac and its contents gradually takes
place and the aneurysm is cured. But in those aneurysms which are
fusiform dilatations of the vessel there is but slight chance of such cure,

for the blood sweeps evenly through it without staying to deposit clot
or laminated fibrine.
In the treatment of aneurysm the aim is generally to lower the blood
pressure by absolute rest and moderated diet, but a cure is rarely
effected except by operation, which, fortunately, is now resorted to
more promptly and securely than was previously the case. Without
trying the speculative and dangerous method of treatment by
compression, or the application of an india rubber bandage, the surgeon
now without loss of time cuts down upon the artery, and applies an
aseptic ligature close above the dilatation. Experience has shown that
this method possesses great advantages, and that it has none of the
disadvantages which were formerly supposed to attend it. Saccular
dilatations of arteries which are the result of cuts or other injuries are
treated by tying the vessel above and below, and by dissecting out the
aneurysm. Popliteal, carotid and other aneurysms, which are not of
traumatic origin, are sometimes dealt with on this plan, which is the old
"Method of Antyllus" with modern aseptic conditions. Speaking
generally, if an aneurysm can be dealt with surgically the sooner that
the artery is tied the better. Less heroic measures are too apt to prove
painful, dangerous, ineffectual and disappointing. For anturysm in the
chest or abdomen (which cannot be dealt with by operation) the
treatment may be tried of injecting a pure solution of gelatine into the
loose tissues of the armpit, so that the gelatine may find its way into the
blood stream and increase the chance of curative coagulation in the
distant aneurysmal sac.
(E.O.)

ANFRACTUOSITY (from Lat. _anfractuosus_, winding), twisting and
turning, circuitousness; a word usually employed in the plural to denote
winding channels such as occur in the depths of the sea, mountains, or
the fissures (_sulci_) separating the convolutions of the brain, or, by
analogy, in the mind.

ANGARIA (from [Greek: aggaros], the Greek form of a Babylonian
word adopted in Persian for "mounted courier"), a sort of postal system
adopted by the Roman imperial government from the ancient Persians,
among whom, according to Xenophon (_Cyrop._ viii. 6; cf. Herodotus

viii. 98)