It is not speaking accurate language, if we say, that in the diseases of this genus the fever is contagious; since it is the material produced by the external membranes, which is contagious, after it has been exposed to air; while the fever is the consequence of this contagious matter, and not the cause of it. As appears from the inoculated small-pox, in which the fever does not commence, till after suppuration has taken place in the inoculated arm, and from the diseases of the fifth genus of this order, where contagion exists without fever. See Class II. 1. 5. and II. 1. 3. 18.
1. _Febris sensitiva inirritata._ Sensitive inirritated fever. Typhus gravior. Putrid malignant fever. Jail fever. The immediate cause of this disease is the increase of the sensorial power of sensation, joined with the decrease of the sensorial power of irritation; that is, it consists in the febris sensitiva joined with the febris inirritativa of Class I. 2. 1. 1. as the febris sensitiva irritata of the preceding genus consists of the febris sensitiva joined with the febris irritativa of Class I. 1. 1. 1. In both which the word irritata, and inirritata, are designed to express more or less irritation than the natural quantity; and the same when applied to some of the diseases of this genus.
This fever is frequently accompanied with topical inflammation, which is liable, if the arterial strength is not supported, to end in sphacelus; and as mortified parts, such as sloughs of the throat, if they adhere to living parts, soon become putrid from the warmth and moisture of their situation; these fevers have been termed putrid, and have been thought to owe their cause to what is only their consequence. In hot climates this fever is frequently induced by the exhalations of stagnating lakes or marshes, which abound with animal substances; but which in colder countries produce fevers with debility only, as the quartan ague, without inflammation.
The sensitive inirritated, or malignant, fever is also frequently produced by the putrid exhalations and stagnant air in prisons; but perhaps most frequently by contact or near approach of the persons, who have resided in them. These causes of malignant fevers contributed to produce, and to support for a while, the septic and antiseptic theory of them; see Sect. XXXIII. 1. 3. The vibices or bruises, and petechiæ or purples, were believed to be owing to the dissolved state of the blood by its incipient putrefaction; but hydrostatical experiments have been made, which shew the sizy blood of the patient in sensitive irritated or inflammatory fever, with strong pulse, is more fluid, while it is warm, than this uncoagulable blood taken in this sensitive inirritated, or malignant fever; from whence it is inferred, that these petechiæ, and vibices, are owing to the deficient power of absorption in the terminations of the veins, See Class I. 2. 1. 5.