Hippocrates points out the danger of opening these tumours indiscriminately. They consist, as Galen remarks, of a viscid and mucous fluid. Galen and Oribasius agree with our author in directing a piece of lead to be bound upon the ganglion. Nearly the same plan of treatment is recommended by Aëtius, who directs us to bind a piece of lead upon the tumour, and after some days to remove it, when the ganglion will be found much softened; it is then to be squeezed firmly between the thumb and the fingers, by which means it will be speedily dissolved. Albucasis approves of extirpating the tumour, unless it be seated near a joint. Rhases as usual collects the opinions of all preceding authorities. Antyllus, he says, directed the surgeon to break the sack, or to bind a heavy plate over it, or to extract it by the knife. When an operation is attempted, he recommends that the surgeon be sure that he has removed the whole sac. He relates a case in which the swelling was dissolved by an application containing mustard. SECT. XVII.—ON PHLEGMON. In general, we call all those swellings phlegmons which are red and painful, and accompanied with heat; some diversity of their nature arising from the cause which occasions them. For when good blood and of moderate consistence rushes abundantly to a part and from its quantity becomes seated in it, the disease is that which is properly called phlegmon; but when yellow bile is seated in a part, it is called herpes; and when blood and yellow bile together are collected in a part, erysipelas is formed; but when in this case the blood is hot and thick, it usually gives rise to carbuncle. Wherefore, we shall begin with what is properly called phlegmon, which occurs in many cases, being a swelling which is red, painful, elastic, and hot, deriving its origin, as I said, from good blood which is sometimes collected from the whole body, and sometimes is formed abundantly in the part itself, so that it cannot be contained in the vessels, but escapes from them in the form of vapour into the surrounding cavities. And this affection supervenes upon wounds, fractures, ulcers, and many other causes. When therefore a part becomes inflamed without any obvious cause preceding it, the whole body sending a defluxion to the part, we must evacuate the general system by venesection, and apply to the part embrocations and cataplasms, not such as are of a heating and moistening nature, but such as are calculated to repel the fluid, which is flowing to the part, and evacuate that which is already contained in it. Apply, therefore, a cataplasm of house-leek, and of the bark of the pomegranate tree boiled in wine, with sumach and polenta: when the pain is not violent, this or such like applications are to be used; but when there is a defluxion to the part with greater pain, then cataplasms of hot water and oil, or of polenta, must not be applied (for all these are inimical to such defluxions); but the vehemence of the