b. Chronic inflammation.—As we find that in phlegmon there is a great tendency to the formation of pus, so in chronic inflammation there is usually a deposition of solid matter, which produces more or less of induration and enlargement. This deposition seems almost in every instance to occur in the cellular tissue, either where it is interstitial, or where it pene trates into the interior of the several organs. This is observed among other parts in chronic inflammation of glands, as the testis, mamma, liver, tonsil, &c. ; in the lymphatic glands, especially in scrofulous persons ; in various dis eases of the joints ; in the hard swellings so often • seen in scrofula, gout, and rheumatism ; in imperfectly cured erysipelas, pellagra, and ele phantiasis; in the callous edges of old ulcers ; in the uterus, labia pudendi, and prepuce of the penis ; and, according to Otto,l' in that pe culiar induration of the cellular tissue which occurs in new-born children. This distin guished pathologist, in common with many other continental writers, attributes phlegma sia dolens to the same cause. The incorrect ness of this opinion has been demonstrated by the researches of Dance,Arnott others. (See VEIN.) The great induration often induced by long continued chronic inflammation was called by the older writers scirrhus ; and even in the present day most of the French pathologists apply that term to the hardness thus induced, as well as to the malignant disease, to indicate which English practitioners restrict the vvord.
The substances that are effused into the cel lular tissue in chronic inflammation are various, according to the part attacked, the circum stances of the disease, constitution, &c. It generally consists of a whitish or greyish matter, of a lardaceous, homogeneous appearance, caus ing what is called by modern pathologists, white induration ; and sometimes it is of a yellowish, or even bluish colour. It is doubtful whether this substance. consists of the fibrine or albumen. of the blood, or of some newly formed material. In scrofulous individuals the deposition consists of the well-known caseous matter, so characteristic of the strumous diathesis; lastly, this form of inflammation, especially in strumous constitu tions, often leads to the formation of chronic abscess, the contents of which, as Gendrin, Mayo, and others have observed, do not, how ever, consist of true pus, but of serum generally mixed with a flakey matter, or even tinged with blood.
c. Spreading or diffuse inflammation.—The cellular tissue, constituting in all parts of the body an uninterrupted secreting surface, is sub ject to spreading inflammation, which, from the extent of the pluts implicated, the disorganiza tion induced, and the alarming character of the attendant constitutional disturbance, must be regarded as one of the most formidable diseases to which the human body is subject. In what
ever manner this disease originates, whether from poisoned wounds, from phlegmonous ery sipelas, from external injury, or from any other cause, it progressively and rapidly attacks a large extent of the cellular tissue, often invading an entire limb, or even a considerable part of the trunk. In examining parts thus affected after death, they are found to be variously altered, according to the duration of the dis ease and the order in which they became in volved ; in those which are most recently im plicated, the cellular substance is merely cede matous, containing a large quantity of limpid or reddish-coloured serum, which readily flows out on making an incision, and which after wards acquires more consistence, and becomes more deeply coloured. In the subsequent stages, pus, sometimes pure, sometimes dis coloured, is effused : the matter is at first con tained in the cells, which are gorged with a whitish semifluid matter, but afterwards dep6ts of matter take place in the disorganized tissue ; there being, however, no proper cyst, owing to the want of that barrier of lymph which is effused in common phlegmon. These abscesses are often numerous, but insulated and distinct from each other : at other times they occupy a great extent, and contain a large quantity of pus, often mixed with shreds of mortified membrane. In the more severe forms of this affection the natural organization is in some places totally destroyed, and the cellular substance, from the effects of gangrene, is converted into a greyish or dark-coloured slough.
These changes are not confined to the sub cutaneous membrane, in which, however, they are principally observed, but are seen in the cellular sheaths of the muscles, and even in the processes which separate their different fasciculi. The muscles themselves, under these circum stances, partake in the disorganization, and lose their proper colour.
The progress of this formidable disease would seem to shew that an acrid and irritating hu mour is effused into the cellular substance, where it rapidly causes suppuration and slough ing, in the same manner as when urine is ex travasated into the perinmum and scrotum. That a vitiated state of the blood is often pro duced is a now well-known fact, and such a condition appears to be induced in the disease under consideration, either in consequence of the introduction of a poison into the system, as from the bite of a venomous serpent, or from a deterioration of the constitution, as in draymen, coal-porters, and others, who in large towns con sume enormous quantities of fermented liquors ; or, lastly, from both these causes combined, as from punctures received in dissection by indi viduals who at the time are in an indifferent state of health.