ANEURYSM

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) it was established by cyrus the great. couriers on horseback were posted at certain stages along the chief roads of the empire, for the transmission of royal despatches by night and day in all weathers. in the roman system the supply of horses and their maintenance was a compulsory duty from which the emperor alone could grant exemption. the word, which in the 4th century was used for the heavy transport vehicles of the cursus publicus, and also for the animals by which they were drawn, came to mean generally "compulsory service." so _angaria_, _angariare_, in medieval latin, and the rare english derivatives "angariate," "angariation," came to mean any service which was forcibly or unjustly demanded, and oppression in general. angary (lat. _jus angariae_; fr. _droit d'angarie_; ger. _angarie_; from the gr. [greek: aggareia], the office of an [greek: aggaros], courier or messenger), the name given to the right of a belligerent to seize and apply for the purposes of war (or to prevent the enemy from doing so) any kind of property on, belligerent territory, including that which may belong to subjects or citizens of a neutral state. art. 53 of the regulations respecting the laws and customs of war on land, annexed to the hague convention of 1899 on the same subject, provides that railway plant, land telegraphs, telephones, steamers and other ships (other than such as are governed by maritime law), though belonging to companies or private persons, _may be used_ for military operations, but "must be restored at the conclusion of peace _and_ indemnities paid for them." and art. 54 adds that "the plant of railways coming from neutral states, whether the property of those states or of companies or private persons, shall be sent back to them as soon as possible." these articles seem to sanction the right of angary against neutral property, while limiting it as against both belligerent and neutral property. it may be considered, however, that the right to use implies as wide a range of contingencies as the "necessity of war" can be made to cover. (t. ba.)