An essay on the comparative merits of artificial and natural classification, as applied to diseases of the skin ... / [John Paget].

  • Paget, John, 1808-1892.
Date:
1833
Catalogue details

Licence: Public Domain Mark

Credit: An essay on the comparative merits of artificial and natural classification, as applied to diseases of the skin ... / [John Paget]. Source: Wellcome Collection.

    19/54 (page 15)
    extent than had ever been previously accomplished. Brought up in the Linnean school, Willan had probably no idea of the purposes of classification beyond the one he proposed to him¬ self, and for this purpose it is impossible he could have chosen any character so well adapted for it as the one he has done ; in¬ deed it almost reminds one of the facility of the great naturalist himself; and it is not improbable that this happy selection of character may retain in use the artificial method in diseases of the skin, as it undoubtedly has done in botany, long after the principles on which it was founded have been shown to be er¬ roneous. Many, however, as are the advantages possessed by the pri¬ mitive form of eruption as the character of a system, we cannot close our eyes to the fact, that it is in itself too imperfect and irregular to be safely depended on. We have already said, and we believe it will be generally admitted, that no other single character pervading the whole class is more constant than the one selected by Dr Willan. If, therefore, we can show that this character is inconstant and inessential, we shall prove, as a ne¬ cessary consequence, the insufficiency of this or any other arti¬ ficial system for the classification of cutaneous diseases. In the first place, the eruption may change its nature and character in the course of its developement. The most com¬ mon instance of this change, is that in which a vesicle, by the augmentation of the inflammation, rendering the base hard and thickened, secretes a white and opaque, instead of a clear and colourless fluid, and thus becomes a real pustule. This is so common an occurrence, that it must have been observed by, and probably at first perplexed, almost every follower of the English system. The papula is not more constant to its original form. Sometimes, though not very frequently, it secretes a small quantity of serum, and assumes the appearance of a vesicle; sometimes it changes its form for that of a scale ; indeed Bate¬ man expressly observes, that in the three first of Wiliam's spe¬ cies of Lichen, the papular form is often lost, and they “ occa¬ sionally pass into Psoriasis while in the fourth species, Lichen Agrius, it is considered a distinctive mark, that “ it is liable to terminate in a chronic pustular disease, the Impetigo The rash or diffuse inflammation of the skin will often, as seen in Erysipelas, exhibit large Bullae, in consequence of the in¬ tensity of the inflammation; so frequently indeed does this * A Practical Synopsis of Cutaneous Diseases, according to the arrangement of Dr Willan, by Thomas Bateman, 6th ed. 1824, p. 11 and 12. It may be as well to observe, that, in speaking of the arrangement of Willan, I always make use of his nomenclature ; in all other cases that of M. Alibert is preferred.