Before referring to the physical signs it might be well to describe the condition and general appearance of the patient when the lungs became involved. The patient who had been progressing with an apparently simple influenza, with no chest signs except those of bronchitis or tracheitis, occasionally slightly cyanotic, became more cyanotic, the elevation of temperature continued longer than three to seven days, or if it came to the normal began to rise again, his respirations gradually increased and the pain in the chest became well localized. One could safely assume that the patient had developed a lesion in the chest. This could not always be localized during the first few hours or on the first day. The evidence of increased bronchial disturbance was frequently recognized, and later impairment of resonance and diminished breath sounds associated with “a few crackles” were noted. This, so far as we can tell, may have been the only evidence of the stage of œdema or “wet lung.” After this, as the disease advanced, definitely increased vocal fremitus and rather definite tubular breathing with greater impairment of resonance were noticed. These signs were usually observed first at the apex of the left lower lobe, and from here they extended forward along the inter-lobar sulcus, or downward along the spinal column. If the lesion was noticed first on the left side, in a day or two it was found more or less definitely in the right lower lobe also. It seemed to occur more frequently first in the body of the right lobe, instead of in the apex of the lobe as on the left side. In both lobes it might spread to contiguous areas and form a massive consolidation, or it might be found in small separate areas, some of which would clear up in a day, while others would persist. The expectoration was frothy, containing either blood or masses of yellowish, greenish purulent material floating in a watery sanguiolent or clear fluid, or enmeshed in frothy mucus. The amount of expectoration in some cases was enormous, but as a rule it was scanty. It was thick and ropy at times and distinctly annoying to the patient.