According to Haly Abbas, hectic fevers commonly arise either from the conversion of semi-tertians, or from abscesses of the lungs, whence heat is sent to the heart, and from it is diffused over the system. (Theor. viii, 7.) Alsaharavius states that hectic fevers arise from protracted ephemeral or putrid fevers, or from sympathy of the system with ulceration of the lungs, bladder, or liver, or from any chronic and prolonged disease. (Pract. xxxii.) Averrhoes represents the hectic as supervening upon ephemeral and putrid fevers. He ridicules the comparison of the effects of food on the febrile heat to those of water poured upon lime. (Collig. iv, 33.) Avenzoar gives the same account of hectic as our author. (iii. 3, c. 13.) Serapion’s account, although borrowed from the Greeks, is distinct and curious (vi, 11.) See also Rhases (ad Mansor. x, 3, _alibique_.) He and Haly Abbas repeat the graphic delineation of a person in the last stage of hectic fever, borrowed by our author from Galen, who seems to have had in view a similar description of a person sinking of consumption, given by Aretæus. (De Morb. Chron. i, 8.) Avicenna’s account of the nature and causes of hectic fevers is so ample, that we regret our limits will not permit us to do justice to it. The principal causes of them which he enumerates are ephemeral and putrid fevers, and abscesses of the lungs and liver. The pulse, he says, is hard, small, frequent, and weak, and may become _myurus_, if the fever pass into the state of marasmus. He gives, principally from Galen (de Marasmo), an interesting description of what he calls the _hectic of old age_, but which Galen calls _old age from disease_. Its symptoms, as described by these authors, are coldness and aridity of the body; the pulse slow, small, and rare, unless very weak; the urine white, thin, and watery. (iv, 1, 3.) Franciscus de Pedemontio, a writer of the fourteenth century, in like manner pronounces the hectic of old age to be a dry intemperament of the system, and recommends for it a calefacient and moistening regimen. SECT. XXXIII.—THE CURE OF HECTIC FEVERS. Those affected with hectic fevers should be well supplied with food from the commencement, on account of the pungency of the humours. The best cure is a moistening diet. You ought therefore to give for nourishment the juice of ptisan, and broths of chondrus, with a little bread in addition; and to treat the patient with a draught, of moderately cold water, when neither inflammation nor putrefaction of the humours is present. But if you conclude that the lesion is great, you must proscribe the cold water, and have recourse to the cooling applications externally. To those affected in this manner, baths are at all times proper. * * * * *