1. Abscessus abdominis. An abscess of the Belly.

See Inflammatio. Musc. Abdom. N° 10.

2. Abscessus ani. An abscess of the Anus. A large quantity of fat fills'up the cavity on each side of the anus, and is the seat of this disorder. The causes are various; as contusions, wounds, inflammations, difficult labour, hard riding, a dysentery, the venereal disease, etc. Abscesses sometimes are suddenly formed in this part; at others they advance very slowly. In the first case the appearances are in the beginning no other than those of a common boil; but the symptoms soon in-crease, quickly proceeding to a more formidable state. In the latter, though the suppuration makes but little progress, the pain and tumour sufficiently determine the nature of the complaint. The pus, whether it makes its way through the skin or through the intestines, is frequently so tedious in its passage, that the adjacent fat is more or less corroded, and sinuses are formed of different shapes and sizes. Sometimes the maturation is extended on every side, rendering the cure both difficult and uncertain. When abscesses in this part are left to themselves, they rarely fail to degenerate into fistulas, and occasion troublesome callosities.

As soon as the tumour is formed, endeavour with all possible speed to bring on suppuration; and, when this is in some degree advanced, procure a speedy discharge. To this end, let the patient stand on the ground with his feet asunder, and lean over a table upon his belly; then the operator, introducing a finger into the anus, will perceive the matter in a fluctuating state; in which case, without waiting for the external signs of suppuration, he will make an opening into it with a knife: by pressing the finger in the anus on the abscess, and another on the external part, a judgment may be formed where to make the puncture; for, by the finger in the rectum, the pus maybe pressed externally, so as to be perceived by the finger there. When the opening is made, endeavour to enlarge the wound as you withdraw the knife; and, for the better application of proper dressings to the bottom, another incision may be made transversely. If the rectum is laid bare, an incision must be made in it also, as far as the accident extends, in order to its reunion with the adjacent parts, for the regeneration of flesh is obtained with great difficulty on the surface of this intestine. When the matter surrounds the anus, the cure is hardly to be performed without cutting off all that is bare. See an extraordinary instance of this kind in the Med. Mus. vol. iii. p. 251. 257.

A proper opening being made, the dressings, etc. are as in abscesses in general. Though Aetius observes, that when this disorder extends round the anus, while the wound is filling up, a constriction of the circumjacent parts, and an obstruction of the passage of the anus occur; to prevent it he advises introducing a canula there, and continuing it till the cure is finished. But how far a good habit of body, with other favourable circumstances, may encourage our hope of success this way, the practitioner can only judge by the circumstances, and his own experience. When the cause is venereal, these tumours suppurate slowly; and without a gentle mercurial ptyalism a cure is hardly to be effected. See Fistula. See Kirkland's Med. Surgery, vol. ii. 201.

3. Abscessus arthriticus. See Abscessus intes-tinorum, N° 17.

4. Abscessus auris. An abscess in the Ear. The symptoms attending an abscess in this part have nothing peculiar, except that the pain is very exquisite. - See Otaglia.

5. Abscessus axillae. An abscess in the Arm-pit. Abscesses are often formed by injuries in the arm, hand, or fingers; and sometimes by a fever. When the fever is of a malignant kind, these tumours suppurate but slowly; and when ripe, an opening should be made with the caustic; or, if great debility prevails, it must be opened more early with the knife. This disorder when it terminates the plague is usually called a bubo, q. v. See also Abscessus In 'guinis, No. 16.

6. Abscessus calcis. An abscess of the Heel. The common causes of an abscess may produce it,but . generally it is from scrofula. If there is a caries, the best method is to pass an actual cautery through a canula. Wiseman says it saves much time, and that thus the caries seldom separates in the form of a scale, but moulders away insensibly with the matter.

7. Abscessus capitis. An abscess on the Head. Wounds on the head generally are the most speedily healed; when an abscess is.brought to the state of a wound, the same advantages attend it, and the common methods suffice for the cure. When abscesses are seated on the sutures, they may be troublesome by inflaming the dura mater which passes through them, and is continued to the pericranium. Every whereon the scalp, a caustic is the best method of opening abscesses., especially if the long confinement of the matter hath rendered the skull carious, for it makes some way for the raspatory, which is always used, except on the sutures: exfoliation here is very slow, therefore rasping is used, and then incarnation can immediately proceed. Abscesses over the forehead are best opened by incision; but care should be taken that the direction of the muscular fibres may be followed, for a transverse wound may cause the eye-lids to fall over the eye. Abscesses on the head are sometimes owing to a diseased bone from a venereal affection, and are then most troublesome, since in these small vessels the action of mercury is for a long time weak and almost imperceptible.

8. Abscessus cerebri. An abscess in the Brain. Instances of this kind have occurred; and if the trepan is used early enough, the case ends well; but it seldom happens that the situation of the abscess can be determined with sufficient accuracy to enable us to employ that instrument, except it is in consequence of external violence. Abscesses, from internal causes, are generally seated in the external parts of the. brain.