134 HEALTH AND DISEASE 



DISEASES OF THE SKIN 

 CLASSIFICATION 



A section on diseases of the skin presents to the writer certain diffi- 

 culties, not on account of the want of material, but rather from its 

 redundancy. The reader may be inclined to observe, speaking from his 

 own experience, that a very limited literature should be sutiicient to deal 

 with the affections which attack the exterior of the animal body. The 

 contrary is in reality the case. Dermatology is a very wide subject, and 

 during the past century a large number of most distinguished medical 

 authorities on the Continent, especially in Germany and France, and also 

 in England, have devoted almost exclusive attention to disorders of the 

 skin. Among the writers in Germany the names of Ferdinand Hebra and 

 Virchow, and in England Willan, Bateman, Erasmus Wilson, Todd Thomp- 

 son, M'Call Anderson, Tilbury Fox, Malcolm Morris, may be mentioned 

 among a host of other distinguished men. Willan's system of classification 

 formed the basis of the other different systems which have from time to 

 time attracted the attention of the scientist, but even some of our modern 

 writers still hold that the system of Willan and Bateman is for practical 

 purposes preferable to what is called the natural and the pathological 

 systems of classification. 



The first attempt to classify diseases of the skin was made by 

 Hieronymus Mercurialis in 1572, by whom skin aflfections were divided 

 according to their locality, as those of the head and those of other parts. 

 This simple ai-rangement was added to by Daniel Turner, in 1743, and by 

 Alibert in 1806, who subdivided the diseases. Scientific classification is 

 said to have begun with Plenck, Vienna, 1776, who took as his basis the 

 oV)jective features of the diseases, grouping Affections of the Skin 

 under fourteen heads: (l) Macules, (2) Pustules, (3) Vesicles, (4) Bullae, 



(5) Papules, (6) Crusts, (7) Scales, (8) Callosities, (9) Excrescences, (10) 

 Ulcers, (11) Wounds, (12) Cutaneous insects, (13) Diseases of the nails, 

 (14) Diseases of the hair. 



This classification to some extent was modified by Willan, who used the 

 terms (1) Papules, (2) Scales, (3) Exanthemata, (4) Bullse, (5) Pustules, 



(6) Vesicles, (7) Tubercles, (8) Macules; and Willan's pupil Bateman added 

 Dermal excrescences. 



Erasmus Wilson adopted an anatomical system of classification, grouping 

 the skin affections according to the structures in which they arose, making 

 four divisions: (l) Diseases of the derma, (2) Diseases of the sudoriparous 



