The _swelling_ is at first very small and tender, but it encreases rapidly, and in a few hours may extend to one, two, or three feet in diameter. At first smooth, rounded, pitting on pressure and destitute of crepitation on handling, it becomes softer and less sensitive and when pressed or kneaded it gives a crepitant sensation and sound, or it even appears to gurgle. When percussed the resonance is drumlike. Finally, the skin may become cold, insensible, and withered like a piece of parchment. When incised the tissues are found to be gorged with blood, and of a black or dark red color; they break down under pressure into a bloody pulp, and from the wound flows a bloody fluid which may be red in the early stages, black in the advanced, and frothy in the latest. Where the connective tissue is very loose and abundant, the bloody extravasation is surrounded by an extensive straw colored œdematous infiltration. The swelling is sometimes single, but more frequently several appear and become confluent. The lymph glands in the vicinity become greatly enlarged. _Fever_ is a constant condition as the swelling advances and sometimes it precedes the local engorgement. There is erection of the hair, with it may be, distinct shivering, recurring again and again. Then general stiffness, dulness, prostration, loss of appetite and rumination, accelerated breathing sometimes attended by a grunt or moan, and rapid pulse. The temperature usually reaches 104° F., and may rise to 109° F. The breathing becomes more and more labored and plaintive, colicy symptoms may set in, the prostration advances to complete adynamia, the patient can no longer stand, the temperature drops to 100° F., or 98° F., and death supervenes in from eight hours to two days from the first sign of illness. In some cases the swelling may be invisible because it is situated deeply or it may perhaps be entirely absent, and the constitutional symptoms are the only ones observed. _Diagnosis._ From _malignant œdema_, which it resembles in producing gas and crepitating tumors, emphysematous anthrax is distinguished by the greater length of the microbe, by its formation of spores at the pole and not in the centre of the bacillus, by the more sluggish motions of the germ, by the restriction of the germ to given infected districts instead of being generally diffused as in malignant œdema, by its not attacking man, rabbit, nor pigeon, which are subject to malignant œdema, by its deadly action on mature cattle which are usually immune from malignant œdema, and by the abundant blood extravasation on the swelling.