In collections of matter not far removed from the surface, the most superficial, and generally the most dependent, portion of the parietes appears inflamed; its inner surface is gradually absorbed; and, when it has thus become attenuated, a portion of the integument sloughs or ulcerates. A communication is established with the diseased parts, through the external surface, thus providing an aperture for the evacuation of the matter—of extraneous substances—or of parts of the body which have either mortified, or otherwise become useless to the system. In such collections, more especially if deeply seated, the matter generally seeks the surface, or extends in the course of the bloodvessels. Cold abscesses, as they are called, often contain as much flaky fibrinous matter as true pus: hence one of the signs of inflammation, swelling, is absent; the fibrin being discharged instead of having been added to the neighbouring parts. As formerly remarked, suppuration occurs much more readily in some constitutions than in others; and patients peculiarly liable to the formation of abscesses, without any great degree of previous excited action of the bloodvessels, are said to labour under _Struma_ or _Scrofula_. These terms are by some used to denote a distinct or specific disease, while others consider them merely as a peculiar state of the constitution. The strumous diathesis is said to be marked by hair and irides of a very light colour, and by the skin being of a peculiar white hue; but, in some instances, the complexion is unusually dark and sallow. The upper lip generally presents a swollen appearance, as also the columna and alæ of the nose. The organization throughout is delicate, and the patient is frequently of a handsome, though infirm, structure. Constitutions, in every respects strong and originally vigorous, may, from various causes, become weak, and present many of the symptoms usually termed scrofulous. I recollect a young patient, born of healthy parents, who had enjoyed excellent health, becoming covered with ulcers and chronic abscesses, in consequence of exposure to cold during menstruation. To the continued irregular and imprudent exhibition of mercurial _alteratives_, as they are called, may be attributed the cachectic and scrofulous constitutions of many thousands of patients of all ages. The strumous diathesis is said to depend upon a want of balance, or proportion, between the solids and circulating fluids. Want of action and power in the organs forming and circulating the blood, disordered digestion, and various other circumstances which it is unnecessary to detail, have also been considered as causes of this state of the constitution.