Albucasis treats of aneurism in the following terms. When an artery is divided, and the skin heals over it, a tumour frequently is the consequence, and the same thing sometimes happens from the wound of a vein. Aneurism of an artery is characterized by a deep-seated tumour in the situation of an artery, the swelling subsiding when pressed upon by the fingers, and being attended with a hissing sound. When it arises from the wound of a vein it is round and exposed. He adds, to open such tumours, especially if seated in the armpits, groins, and neck would be a fatal mistake. When the aneurism arises from dilatation of the artery, we are to make a longitudinal incision, and having dissected away the artery from the surrounding parts, to pass below it a needle armed with a double thread, and to tie the threads in two places as recommended in angiology. The part between the two ligatures is then to be divided and the blood evacuated. Suppurative applications are then to be made, until the ligatures fall out; after which suitable ointments are to be applied. If the disease arise from the opening of a vein, we are to grasp as much as possible of the tumour in the hand, to push a needle through it armed with a double thread, when the aneurism is to be firmly bound with the threads in the manner described in the operation for staphyloma. When danger is apprehended from the falling out of the threads, we are to introduce another needle armed with another thread under the whole tumour at the opening made by the first needle, and to tie the threads in four places. The aneurism is then to be cut in its middle, and its contents evacuated, when the superfluous skin is to be removed, and a compress dipped in wine and oil applied. (Chirurg. ii, 49.) The threads which he speaks of are meant to decussate one another like the letter Χ. This part of his description is somewhat obscure. We need scarcely remark that the operation of Albucasis is exactly the same as our author’s. Rhases borrows his account of aneurism from Antyllus and Paulus. The operation of Antyllus consisted of tying the artery above and below the tumour, and then evacuating its contents. (xiii, 7.) He states that when the disease occurs in the hams, groins, or neck, it is dangerous to meddle with it, but that when seated in the extremities it is easily cured. All the cases in which he had known the artery to be opened during the performance of venesection had terminated in aneurism, except one in which a cure was effected by compression. (Cont. xxviii.) Haly Abbas directs us when an artery has been wounded in bleeding, to dissect away the parts about it, and having applied a silk thread on each side of the wound, to divide the artery in the middle. When an aneurism takes place he recommends a plan of treatment similar to that recommended by Albucasis. (Pract. ix, 45.)