creased during inspiration. The patient lies with difficulty on his side, and the cough is very painful, at first dry and afterwards moist, often bloody." (Op. cit. note by Bosquillon, vol. i, pp. 376 and 377).

The characters here assigned by Bosquillon to pleurisy and to peripneumonia are not without importance. Thus the hard pulse has been indicated as properly belonging to pleurisy, by several authors, and among others by Baglivi, who thus expresses himself: "Si vis cognoscere pleuritidem, præcipuam curam in natura pulsus cognoscenda reponito: pulsus durities est signum fere infallibile omnium pleuritidum; et dum obscuræ sint pleuritides, vel aliis complicatæ pectoris morbis, si duritiem (id est nimiam arteriæ tensionem vibratonemque), in pulsu deprehenderis, quamvis reliqua earum signa non adsint, pro certo habeas patientem laborare pleuritide, &c." (Op. cit. lib. i, cap. ix, de Pleuritide).

The softness of the pulse in pneumonia has likewise been pointed out by most authors, and Dehaën particularly gives us a very ingenious explanation of it. But a distinctive character of the two diseases, far more essential than the state of the pulse, especially as it is more easily appreciable, is the pungent pain, "sometimes limited to a part which may be covered by the finger." This local and fixed pain essentially distinguishes pleurisy from pneumonia. The difficulty of lying on the affected side, is also one of the characteristic signs of pleuritic inflammation; but is it always very easy to distinguish between it and the difficulty of respiration in other than the upright posture which Bosquillon notices in pneumonia? Lastly, I ask, are these characters, however just in themselves, sufficient to guard the practitioner against the commission of error?

A little further on, Bosquillon points out vomica and empyema as ordinary results of pneumonia. A vomica may be recognized by the continuance of the cough and dyspnoea, the impossibility of lying on the affected side, and the development of hectic fever. In case of empyema, the cough, difficulty of respiration and lying in the recumbent posture are

present, there is likewise hectic fever; the patient often feels at the same time a kind of fluctuation produced by the liquid contained in the chest. With the exception of this last symptom, all the others enumerated by Bosquillon have very little value in the diagnosis; and does this last always exist? When Bosquillon pointed it out, was it from clinical facts that he did so, or was he not unwittingly influenced by the remembrance of the Hippocratic succussion? However this may be, the sign but very rarely exists, since we shall hereafter see in speaking of pneumo-thorax, that, in order to the success of the Hippocratic succussion, there must be in the pleura both air and pus at the same time, the only circumstances under which the latter can be agitated and made to give out the noise of fluctuation mentioned by Bosquillon.

Finally, he adds, the signs of hydro-thorax are superadded to these symptoms, and the former he enumerates as follows: "The signs which characterize hydro-thorax, are dyspnoea, pallor of the countenance and oedema of the extremities; the patient experiences great difficulty in keeping the recumbent posture, he starts in his sleep and complains of palpitations. There is a perceptible fluctuation in the chest." (Cullen, op. cit., note by Bosquillon, vol. iii, p. 293.) Apart from the fluctuation of which I have just been speaking, this symptomatology is exact; but it is insufficient. It offers no means of ascertaining in which side of the chest the effusion exists, nor its extent. Moreover, there is not one of these symptoms which is not in like manner produced by a serous effusion in the pericardium; and a diagnosis founded on these data alone, without seeking new elements elsewhere, would necessarily be uncertain, imperfect, and unsatisfactory to all. Sydenham has treated of pleurisy and pneumonia; but he regards both as the result of an inflammatory state of the blood: "When the febrile matter throws itself on the pleura or the intercostal muscles, it ordinarily happens in the commencement of the fever, the morbific matter being yet crude, and not having had time to undergo the necessary concoction and preparation, to be evacuated by the suitable outlets.

The common cause of this occurrence is the improper use of heating remedies." (Sydenham, Pract. Med., translation of Jault, p. 249.) Of course he attached but little importance to the recognition, during life, of the development and even the precise seat of anatomical alterations, which he regarded as the consequence only, and not as the producing cause of the fever. However, he clearly indicates the painful stitch in the side as one of the essential signs of pleurisy; and his translator, M. Jault, endeavoring in a note to give precision to the signs by which the existence of adhesions between the lung and corresponding pleura is recognized, thus expresses himself: "The symptoms which enable us to judge most certainly whether there be adhesion, is when the patient can lie on but one side, without pain and with a tolerably easy respiration. The adhesion is always on the side on which the patient lies easily." (Op. cit.. note by Jault, p. 248.) M. Jault supports this opinion by two reasons: 1st, that when the patient lies on the sound side, the lung tending by virtue of its weight to separate from the costal pleura, the adhesions are put on the stretch; 2d, that in the decubitus on the healthy side, the sound lung cannot supply the unsound lung in its functions. These signs are very rational, but they can only authorize the suspicion of adhesions between the lung and the corresponding ribs; they are not sufficient to render their existence certain. We know that in investigating the effects of these adhesions and the characteristic signs by which they are revealed, Laennec discovered that their constant effect was to diminish that side of the chest which had been the seat of the pleurisy, the consequences of which they were; this furnished a pretty characteristic sign. But to dwell longer on, this subject would be leaving the question which the programme has so precisely limited to the improvements that auscultation has made in the diagnosis and treatment of diseases of the chest. I continue my review of the nosologists who preceded Laennec.

The two diseases we are now considering are frequently discussed in the Practical Medicine of Stoll, But in his con

stant and almost exclusive eagerness to pursue the bile, and the crude and acrid matters of the primæ viæ, the practitioner of Vienna is much more frequently engaged in the search of signs to prove their complication with a bilious state, than in looking after the characters that might serve to distinguish them. Moreover, what he says of pleurisy and bilious pneumonia observed in April, 1776, proves that he regarded them as two different degrees of one and the same malady. This observation," he says, "is important in the diagnosis: that in bilious pleurisy and pneumonia the pain is rarely increased by coughing, or during inspiration; whilst those who are attacked with true inflammatory peripneumonia, can neither cough nor respire without a violent pain in the side. Besides this, the sputa is rarely tinged with blood in bilious pleurisy, unless it be sufficiently violent for the efforts of coughing to bring away a little blood." (Stoll, Pract. Med. translated by J. Terrier, vol. i, p. 65.) Elsewhere, speaking of the importance of the redness of the face, in distinguishing false pleurisy from true inflammation of the lungs, after having examined passages from Baillon and Hippocrates on this subject, he arrives at this conclusion: "that persons are seen affected with pneumonia, whose lungs are attacked by a true and violent inflammation, although the face be very pale, &c." (Op. cit., vol. i, page 68.) From all this does it not appear very evident, that, in his view, pleurisy and pneumonia are the same thing? are not the two words used indifferently by him, at random, so to speak, without any motive to justify the employment of one or the other? Leaving very soon the description of these diseases, Stoll, in the remainder of the passage which I am analysing, busies himself in pointing out the indications for tartar emetic, a remedy which he is known to have used almost exclusively, although he was far from regarding it as contra-stimulant; and I can legitimately conclude that he has in no wise advanced the diagnosis of these two diseases.

Morgagni has devoted two letters (the 20th and 21st) of his immortal work, De sedibus et causis morborum, etc., to the study of pleurisy and pneumonia, under this title: Of pain in

the chest, sides and back. The illustrious founder of pathological anatomy had opened too many dead bodies to be in danger of falling into similar errors respecting the nature and seat of these two phlegmasiæ. He is seen, in the remarks which always follow each history, endeavoring to show that the part where the patient had felt the pain, is invariably the same at which the lung is found adherent to the pleura; that in cases of peripneumonia, the pain is always gravative, whilst in cases of pleurisy it is more acute and pungent, on account of the great number of nervous fibres which terminate in the pleura. (Op. cit., translated by Désormeaux, vol. iii. page 305). However, when the real opinion of Morgagni on the nature of these two phlegmasiæ, is sought for, it will be found that he does not think they can exist separately, except it be to a very slight extent. We find him, indeed, in his 21st letter, accumulating authorities to prove that a pleurisy cannot cause death, without the phlegmasia extends itself to the lung. "Hippocrates, in his book De locis in homine, has positively placed in the lung not only the seat of peripneumonia, but also that of pleurisy. Calius Aurelianus teaches, with Praxagoras, Herophylus and Euryphontes of Gnidus, that the lung is the part that suffers in pleuritic patients." Further on he cites the observations which Hoffman says were made in the hospital Santo Spirito, at Rome, by Servius, on three hundred patients affected with pleurisy, "among whom he constantly saw one lobe of the lung putrified and filled with matter, whilst the pleura absolutely had no appreciable lesion, or was but slightly altered in any way." Still further on he cites Riviere, in whose Sepulchretum these words are found: "The very violent pleurisies,which ordinarily induce death, degenerate most often intu peripneumonias," and Triller, a most worthy physician, who assures us that generally, "in a true pleurisy there exists not merely an affection of the pleura, as has been heretofore foolishly believed, but likewise a simultaneous alteration of the very substance of the lungs, as anatomy, the only light of medicine, clearly teaches;" and lastly, the great anatomist Haller, who says, "that he has never thought an inflammation of the pleura alone killed any man." (Op. cit.,