object; it often wanders from one to another subject. At the same time there is a feel of weariness which resists the disposition in the patient to change his place and posture, and resists the disposition of the mind to alter the object of its attention, rendering the wish for such changes ineffectual. With these arises an actual inability of exerting the muscular powers, or performing any of the functions of the body; and also an actual inability of exercising the great faculties of the mind, the powers of perception, memory, arrangement of ideas, and of the judgment, in the same degree that they existed in health. The degree in which these take place is extremely different in the attacks of different fevers; but these appearances are _very rarely_ absent, although indeed they may also happen in other diseases.” [58] A _Pathognomic_ symptom is one which being present _certainly_ indicates the presence of a disease, and being absent, the contrary. [59] Vol. iv, p. 123. Dr. Rush accounts the lassitude with which fever begins, one of the transient phenomena of it; and this with other phenomena he calls _symptoms_. Such as are more permanent and fixed, and which by other writers have been reckoned different species, he calls _states_; and of these he enumerates forty. Such as have any relation to the plague are as follow. I. The MALIGNANT state, known by attacking frequently without a chilly fit, is attended with coma, a depressed, slow or intermitting pulse, and sometimes by a natural temperature or coldness of the skin.... This depressed state of fever more frequently when left to itself terminates in petechiæ, buboes, carbuncles, abscesses and mortifications, according as the serum, lymph, or red blood, is effused in the viscera or external parts of the body. 2. The SYNOCHA, or common inflammatory state; attacking suddenly with chills, succeeded by a quick, frequent and tense pulse, great heat, thirst, and pains in the bones, joints, breast or sides. 3. The BILIOUS state of fever; known by a full, quick and tense pulse, or by a quick, full and round pulse without tension, and by a discharge of green, dark coloured or black bile from the stomach and bowels. This state sometimes assumes the form of an hectic; the patient feels no pain in his head, has a tolerable appetite, and is even able to sit up and do business. 4. The TYPHUS state; known by a weak and frequent pulse, a disposition to sleep, a torpor of the alimentary canal, tremors of the hands, a dry tongue, and, in some instances, a diarrhœa. Sometimes it assumes symptoms of synocha on the eleventh, fourteenth, and even twentieth days. The common name of this state is the _nervous_ fever. 5. Intermissions, or the INTERMITTING and REMITTING states, occur most distinctly and universally in those which partake of the bilious diathesis. 6. The SWEATING state occurs not only in the plague, but in the yellow fever, small pox, pleurisy, rheumatism, hectic and intermitting states.