B. The breathing is weaker on the more resonant side, or ab sent.
a. The resonance is not tympanitic, but is remarkably clear, with great elasticity; if any breathing be audible, it generally consists of a long, distant, blowing, expiratory sound ; there is no voice-sound. Here we have decidedly emphysema of the upper lobe of the affected side. • b. The resonance is tympanitic, and at the same time clear ; the breath-sound is simply weak and distant, its rhythm not ne cessarily altered ; the voice-sound varies. Such is the effect produced by a small portion of air confined in the pleura; a rare circumstance which sometimes follows on paracentesis, and has even been alleged to be the result of spontaneous development.
e. In some cases of pneumothorax, while the percussion reso nance is tympanitic with a wooden tone, the amphoric breath and voice-sounds may not be heard, or only heard at a distance ; either because the opening is temporarily closed, or is situated at some other part of the lung; these cases can only be rightly judged of by comparison with the remainder of the chest.
§ 3. There is little difference on percussion, and no resistance on either side.
A. The breathing is loudest on the duller side.
a. Its rhythm is altered, the expiratory sound is especially pro longed, loud, and harsh ; the voice-sound is also louder than on the more resonant side, which seems to approximate to the healthy standard. We have here a less marked form of consolidation; most probably, from its situation, tubercular, but possibly due to other causes.
b. Its rhythm is natural. On the opposite side the inspiratory sound is deficient, and the expiratory sound is prolonged, but without any degree of harshness, any change in quality being rather indicated by softness and weakness • the voice-sound is louder on the duller side, but not exaggerated, while on the other it is weak or almost absent. This is sufficient to prove that the disease is on the more resonant side, and that the condition is one of dilatation.
B. The breathing is weakest on the duller side. Its rhythm is altered, it has a wavy or jerking character, and the expiration is prolonged ; the voice-sound, in contrast to the preceding case, comes out much more loudly on that side on which the breathing is deficient. The condition is one of commencing consolidation.
§ 4. Percussion fails in detecting any difference between the two sides of the chest.
A. Both lungs may be in their natural condition at this part ; the ratio of the inspiration and expiration corresponds on either side, as well as the loudness of the voice-sound, and all comes within the limits of health.
B. The resonance on both sides may be exaggerated; the chest remarkably rounded and resilient, and moving very little in respiration; the upper ribs not descending as far as they ought in expiration, while in inspiration the lower ribs are usually drawn inwards ; the inspiratory sound is short and deficient, itnd the expiratory prolonged and distant; the voice-sound more or less abolished, as the disease affects chiefly the upper or lower part of the lung. Such are the physical characters of emphysema affecting both lungs.
c. Both sides may be duller on percussion than in health.
a. The deficient resonance may depend upon loss of elasticity of the ribs, and the breathing may still be natural and equal on both sides, or it may have undergone some modification and be accompanied by superadded sounds. The probability of such an explanation being correct must be judged of by the age of the patient ; the exact condition of the lung can only be determined by the nature of the superadded sounds.
b. The dulness may be caused by consolidation, and the charac ters of the breath and voice-sounds are necessarily changed. When the disease is so decided that the dulness is quite unques tionable, I believe it is never equal on both sides ; the condition of that side on which it is most advanced will correspond to one of the first divisions in § 1, when other morbid sounds rarely fail to give indications of disease : when the dulness is slight, the prin ciples of diagnosis are the same as in the next subdivision.