Pleurisy terminates either in resolution, suppuration, or gangrene. The former is the ordinary and most favourable issue. The last occurs rarely, and Laennee has seen only one instance of it from acute inflam mation. Suppuration, however, is by no means uncommon, in which case, says Aretleus, "shivering fits ensue, and lancinating pains, accom panied with a desire to sit in an upright posture ; the breathing gets worse, and there is great fear lest the lung, by suddenly drawing in the purulent matter, should produce suffocation, after the previous and greater danger has been escaped : should the matter, however, burrow between the ribs and separate them, and either point externally or burst into the bowels, the patient usually recovers." With respect to the treatment, perhaps there is no disease in which profuse bleeding from a large orifice has been so generally recom mended by practitioners of all ages and all nations; the only question which has ever arisen upon the subject being, whether the blood should be taken from the side affected, or from the opposite. Hippo crates, and most of the earlier Greeks, recommended the former, while the latter method was practised by Archigenes (' ap. Actium,' tetrab, ii., serm. 4, cap. 68), Avicenna (' Canon.,' lib. iii., fen. 10, tract 5, cap. 1), Avenzoar Teisir; lib. i., tract 16, cap. 3, p. 23, D., ed. Venet., 1549), and their followers in the middle ages. The dispute, which is one of those that have been settled by the discovery of the circulation of the blood, was before that time (as may easily be imagined) considered to be of the greatest consequence, and at the beginning of the 16th century raised a kind of civil war (as Ilayle says) among the Portu guese physicians on account of the controversy between Denys and Brissot, the particulars of which are too curious to be altogether omitted. The dispute was brought at last before the tribunal of the university of Salamanca, where it was canvassed in a most profound manner by the body of physician's; but in the meantime the partisans of Denys, who were the more powerful, obtained a decree from the civil authorities forbidding physicians to bleed on the same side on which the pleurisy was. At last the university of Salamanca gave judgment, and decided that Brissot's opinion was the pure doctrine of Hippocrates and Galen. The other party removed the cause before the Emperor Charles V., 1529, and were not satisfied with exclaiming against the doctrine of Brissot as false, but declared it to be impious and deadly, and that it was no less pernicious to the body than Luther's schisms to the soul. Unluckily for them, just about this time Charles Ilf., duke of Savoy, happened to die of a pleurisy, after having been bled pursuant to the practice which Brissot had opposed. This put a stop to the appeal to the emperor ; but books were written on the question in all parts of Europe, and the practice of the Arabians was generally condemned. A list of these treatises is given by Rend Moreau, in the Life of Brissot, prefixed to his edition of his work ' De Incisiono Vent° in I'leuritide Morbo; &c., Paris, 1622, 8vo. (See Bayle, art. Brissot; from whom the above aecouut is abridged.) But after all this absurd discussion, there are some cases of pleurisy that will not bear bleeding, and the lancet is now much less had recourse to than formerly.
Besides blood-letting, which may assume the form of cupping and leeches, the usual antiphlogiatic remedies, such as saline diuretics, diaphoretics, purgatives, mereurials, blistering, &e., may be employed ; fn cases of acute pleurisy, the operation of paracentesis thoracis is very seldom had recourse to, and is hardly over attended with more than a temporary relief.
Chronic pleurisy is either the continuation, as it were, of the disease in its acute form, or else exhibits at no period either the intense fever, the violent pain, or energy of reaction which characterises an acute disease. In this latter form it creeps on very insidiously, without much acceleration of pulse or heat of skin ; the pain in the side amounts to no more than a mere soreness ; and the difficulty or hurry of breathing is sometimes so inconsiderable as not to attract the indi vidual's attention. However, his unhealthy pallid appearance, his loss
of appetite, and languid look, emphatically tell of mischief going on ; and upon close examination it is found that the absence of fever is not constant, but that towards evening there is a febrile movement.
The anatomical characters of chronic pleurisy do not differ very widely from those of the acute form, especially when it has been a mere transition of one form of the disease into the other. The fluid effused, however, partakes more of a purulent character, and the false membrane is firmer and more condensed, owing perhaps to the longer time it has been under the pressure of the effused fluid. The lung too is more compressed than in acute pleurisy, so much so that there is sometimes a complete annihilation of its vesicular structure, and .the organ itself is reduced to a thin lamina, not exceeding six lines in thicknese, lying down along the spine.
The prognosis of chronic pleurisy is, generally speaking, very unpromising : in the ordinary course of the disease a slow wasting fever sets in ; there is a gradual emaciation ; the appetite fails ; the pulse is languid, although not much quickened ; the legs swell, and the face becomes puffed ; the expectoration often has a disagreeable alliaceous smell. Under these symptoms well-defined hectic fever soon supervenes, and rapidly wears down the patient.
The treatment of chronic pleurisy differs (as might be supposed) very materially from that of the acute form of the disease. Blood letting is hardly ever resorted to, for the weakened habit of body will not bear the exhaustion of it. For promoting the absorption of the effused fluid, as well as for preventing its further secretion, external applications, comprehending the different modifications of counter irritation, for example, blisters, setons, issues, stimulating liniments, &c., appear to be most efficacious. In some cases however the operation of paracentesis thoracis seems to be the last resource, and this so often fails that it is by some practitioners considered an almost hopeless experiment. In trying to improve the habit of body and to relieve the constitutional symptoms, which most commonly accompany this form of the disease, recourse must be had to a nutritious but not a heating or exciting diet, and to the cautious exhibition of such tonics as the patient is able to bear. Change of air is often productive of the moat decided benefit, and sometimes effects an almost instantaneous amelioration in the symptoms, by causing the night perspiration to cease, the appetite to and the sleep to become refreshing.
(See, besides Good, Study of Med., and Law, art.
in Cyclop. of Pratt. Med. (from which two works much of this article is abridged), Cruveilhier, art. Pleurdsic; in Diet. de Ned. Prat., 1835, and Laennec On Diseases of the Chest, translated by Forbes. Besides the ancient authors already quoted, the following references are given by Mr. Adams, in his Corumentary to Paulus iEgineta Celsus, De Med., lib. iv., cap. 6; Paeans De Pict. Ratione ; Oribasius, Collects Afediein., lib. ix., cap. 7, 8 ; Joannes Actuarius, Meth. Med., lib. fv., cap. 4 ; Theophanes Nonni's, cap. 129 ; Cxlius Aurelianus, :De Morb. Acta. lib. ii., cap. 13 ; Octavius Horatianus, ]ter. bled., lib. ii. cap. 4 ; Marcellus Empiricus, De Medicare., cap. 24; Serapion, Pratt., ii. 21 ; Mesue, De