(From febreo, pro ferveo, to be hot). Since the complaints of mankind have attracted the attention of practitioners, the cause of fevers has been a problem that they have in vain attempted to solve; and even the disease itself they have not been able to discriminate by any constant pathognomonic symptom. From the etymology of the term, its essence is supposed to consist in heat; but the skin is sometimes cold: in quick pulse; but the pulse is occasionally slow: in preceding horror; but such a symptom is often unobserved or absent. Critical pathologists have filled pages with such (we think idle) disquisitions; but every physician has been able to distinguish fever by at least some of these symptoms, or a comparison of the different ones; and, among the innumerable mistakes and blunders that we have witnessed, we believe in no one instance has error been found to arise from mistaking fever. Within this fortnight we saw a woman of 82, generally allowed to be in a fever; but the pulse was only 70, the skin cool, the countenance apparently unchanged: it was, however, easy to perceive, from the peculiar feel of the pulse, that it was in a morbid state, and the skin of the palms was tense. She recovered rapidly, the pulse sunk to less than 60, the skin became more genially soft, and the appetite returned.

Dr. Cullen establishes a class of febrile diseases which he styles pyrexiae. The symptoms assigned are, "after chilliness, a frequent pulse, increased heat, several of the functions of the body injured; the strength of the limbs particularly diminished."fever, more strictly, is "pyrexia, with preceding languor, lassitude, and other signs of debility, without any local disease."dr. Fordyce, though he has refined too much, and raised imaginary difficulties in the application of every definition of fever, has, however, shown that these symptoms will not entirely and completely distinguish febrile diseases. One almost constant symptom may be added, a tension of the tendons of the wrist; and we are fully of opinion, with Dr. Fordyce, that in every fever there is some mental alienation. If these two symptoms are added, the definition will be as complete as the most minute pathologist would require. The distinction will be, however, assisted by a more full description of the symptoms.

Previous to the attack of every fever, if it do not come on during sleep, or the attention is not directed very strongly to some interesting object or occupation, lan-and debility are felt, with a sluggishness in motion, and some uneasiness in attempting it. The face and extremities become pale; the features sunk: the bulk diminished; and the skin appears as if constricted by cold. Cold now comes on in the back, as if cold water was running down it, and soon extends over the whole body; though, in some instances, the patient will feel to another person warm. The cold increases to tremor; and this to rigors and shiverings,almost convulsive. Even at this period, the mind is unsteady and confused; attention and recollection are difficult; and stupor is sometimes an early symptom. The pulse becomes weaker, and even sometimes slower, than before; but as the cold increases, it is always smaller, and almost constantly quicker. The respiration is, at this period, small, frequent, and laborious; appetite ceases; a nausea, sickness, and vomiting, come on; and, at last, the matter discharged is highly bilious. The secretions are, in general, checked; the urine is watery; the mouth dry and clammy; ulcers no longer discharge; and tumours diminish or disappear. In the cold stage, frequently, though more often in the hot, headach comes on; but a constant symptom, though not sufficiently noticed by pathologists, is wandering pains over the whole body. Pain in the back is generally mentioned; but pains are felt in every joint, seldom continuing in any one part, but disappearing and returning. They are not sharp and pungent, but tensive and dull; evidently connected with the tension of the tendons, chiefly distinguished at the wrist. A striking change takes place in the features. In general they appear to be sunk; but this description is by no means sufficiently precise. It has not been with accuracy noticed how greatly the appearance of the features depends on the state of the mind: it is the latter which gives character, and a different effect to features otherwise similar. It is sufficient in this place to remark, that the change in the countenance is the absence of all characteristic impression, a vacant stare, accompanied with a kind of insensibility. This attends fever so often, or rather so universally, in every stage, that the existence of the disease may be thus known in a moment by a practitioner of even slight experience.

The continuance of the cold stage is uncertain. The coldness previous to the shivering is, in the worst fevers, of long duration, and the shivering slight. In general the shivering soon comes on; and after a time, different in almost every case, it seems to remit or alternate with slight flushings. In this interval we have thought, by our own feelings, that the disease had disappeared; and we have even remarked that the powers of the mind have, for a short period, returned. The scene, however, soon changes. The alternate flushings become violent heat; the skin again fills; the face becomes turgid; the mind again confused, and this confusion often increases to delirium; the pulse becomes more regular, hard, and full; the respiration more free, but still frequent and anxious; the thirst increases; the vomiting abates; the urine becomes of a deep red, and gives pain in the discharge; tumours again enlarge; and pus flows from ulcers. The sensibility is recovered, and often increased; the headach becomes excruciatingly violent.

After an uncertain period these symptoms abate. Sweat gradually breaks out, and soon becomes profuse. The urine deposits a copious sediment, all the painful symptoms disappear, and health is apparently restored, with the exception only of some remaining debility.