_Description and Definition._--Fever is a powerful effort of the vital principle to expel from the system morbific or irritating matter, or to bring about a healthy action. The reason why veterinary practitioners have not ascertained this fact heretofore is, because they have been guided by false principles, to the exclusion of their own common experience. Let them receive the truth of the definition we have given; then the light will begin to shine, and medical darkness will be rendered more visible. Fever, we have said, is a vital action--an effort of the vital power to regain its equilibrium of action through the system, and should never be subdued by the use of the lancet, or any destructive agents that deprive the organs of the power to produce it. Fever will be generally manifested in one or more of that combination of signs known as follows: loss of appetite, increased velocity of the pulse, difficult respiration, heaving at the flank, thirst, pain, and swelling; some of which will be present, local or general, in greater or less degree, in all forms of disease. When an animal has taken cold, and there is power in the system to keep up a continual warfare against encroachments, the disturbance of vital action being unbroken, the fever is called pure or persistent. Emanations from animal or vegetable substances in a state of decomposition or putrefaction, or the noxious miasmata from marshy lands, if concentrated, and not sufficiently diluted with atmospheric air, enter into the system, and produce a specific effect. In order to dethrone the intruder, who keeps up a system of aggression from one tissue to another, the vital power arrays her artillery, in good earnest, to resist the invading foe; and if furnished with the munitions of war in the form of sanative agents, she generally conquers the enemy, and dictates her own terms. While the forces are equally balanced, which may be known by a high grade of vital action, it is also called _unbroken_ or _pure_ fever. The powers of the system may become exhausted by efforts at relief, and the fever will be periodically reduced; this form of fever is called _remittent_. By remittent fever is to be understood this modification of vital action which rests or abates, but does not go entirely off before a fresh attack ensues. It is evident, in this case, also, that nature is busily engaged in the work of establishing her empire; but being more exhausted, she occasionally rests from her labors. It would be as absurd to expect that the most accurate definition of fever in one animal would correspond in all its details with another case, as to expect all animals to be alike. There are many names given to fevers; for example, in addition to the two already alluded to, we have milk or puerperal fever, symptomatic, typhus, inflammatory, &c. Veterinary Surgeon Percival, in an article on fever, says, "We have no more reason--not near so much--to give fever a habitation in the abdomen, than we have to