THE LIBRARY 
 
 OF 
 
 THE UNIVERSITY 
 OF CALIFORNIA 
 
 PRESENTED BY 
 
 PROF. CHARLES A. KOFOID AND 
 MRS. PRUDENCE W. KOFOID 
 
Graphotype. 
 
 IS 
 
 PARASITIC FUNGI. 
 
PARASITIC OR GERM THEORY 
 
 OP DISEASE: 
 
 THE SKIN, THE EYE, AND OTHER AFFECTIONS; 
 
 BY 
 
 JABEZ HOGG, 
 
 - 
 
 Surgeon to the Royal Westminster Ophthalmic Hospital; Ophthalmic Surgeon 
 
 to the Royal Masonic Institution ; Consulting Ophthalmic Surgeon to 
 
 the Hospital for Diseases of Women and Children, Vincent Square 
 
 late President of the Medical Microscopical Society, and Vice-President of tii& 
 
 Medical Society, London; Hon. Fellow of the Academy of Sciences, Phila>telp}iia, 
 
 and of the Belgian Microscopical Society; F.R.M.S., &c. cfec. 
 
 
 SECOND EDITION. 
 
 *&? 
 
 Ifrmtow : 
 BAILLIERE, TINDALL, AND COX, 
 
 KING WILLIAM STREET, STRAND. 
 
 PARIS AND MADRID. 
 
 '1876. 
 
 / 
 
Works by the same Author : 
 A MANUAL OF OPHTHALMOSCOPIC SURGERY ; 
 
 A TREATISE ON THE USE OF THE OPHTHALMOSCOPE IN DISEASES OF 
 THE EYE. 
 
 THE MICROSCOPE, ITS HISTORY, CONSTRUCTION, AND 
 APPLICATIONS. 
 
 ELEMENTS OF EXPERIMENTAL AND NATURAL 
 PHILOSOPHY, ETC. 
 
PREFACE TO FIRST EDITION. 
 
 IT has frequently been suggested to me that my 
 papers " On the Vegetable Parasites infesting the 
 Human Skin," together with some others on " The 
 Fungoid or Germ Theory of Disease," which lie scat- 
 tered through the serial publications of 1859 to 1872, 
 possess sufficient interest to warrant a re- publication 
 in a collected form. Investigations made in connection 
 with the question of a fungoid theory of disease having 
 occupied much of my time and attention, it will lie seen 
 that in this collection of papers I have endeavoured to 
 bring together matters of interest bearing upon the 
 infective nature and character of certain diseases in 
 relation to the public health. 
 
 1, BEDFORD SQUARE, 
 August 1st, 1873. 
 
DESCRIPTION OF PLATE. 
 
 FIG. ' 
 
 1. Fungi, taken on a glass slide exposed to a current of air. 
 
 2. Algoid. filaments growing in distilled water. 
 
 3. Healthy yeast-cells from sweet-wort, a little too dark in colour, 
 
 and too full of granular matter. 
 
 4. Exhausted yeast, from the bottom of a porter vat. 
 
 5. A tuft of penicillium glaucum. 5a. Spores more highly magnified. 
 
 6. Achorion Schb'nleinii, from a favus crust ferment in sweet -wort. 
 
 7. Achorion Schonleinii, from sweet-wort freely exposed to light ; 
 
 penicillium mycelia, spares, and bacterium-like bodies growing 
 in the same. 
 
 8. Microsporon Audouini, from a case of alopecia. 
 
 9. Fungoid spores and epithelium cells surrounding a hair, from a 
 
 case of alopecia. 
 
 10. Tricophyton tonsurans, from a ringworm crust, 
 
 11. Microsporon furfur, from a case of pityriasis versi color. 
 
 12. Microsporon mentagrophytes, from the beard of a patient suffering 
 
 from sycosis. 
 
 13. Fungus spores and mycelium, from a case of psoriasis. 
 
 14. Fungus mycelium and epithelium scales, from a case of lepra. 
 
 15. Fungus mycelium and epithelium scales surrounding a hair, 
 
 from a case of eczema. 
 
 16. Fungus spores, from a case of lichen. 
 
 17. Fungus spores and mycelium, from a case of tinea tarsi. 
 
INTRODUCTION. 
 
 SINCE the publication, in a collected form, of my 
 papers on "The Fungoid or Germ Theory of Disease," 
 a somewhat remarkable discussion has taken place on 
 the subject in the Pathological Society of London, and 
 which on the whole appears so very confirmatory of the 
 views I promulgated in 1859, and subsequently, that I 
 am tempted to give a brief resume of the question as it 
 now stands. 
 
 I may ' state that soon after the publication of 
 Professor Tyndall's letters in the Times, on the " Germ 
 Theory of Disease," in April, 1870, Dr. Angus Smith, 
 who had long held somewhat similar views on the 
 question, stated at a meeting of officers of health, 
 that he was no longer able to believe in the germ 
 theory. Considering that Dr. Smith had long held 
 certain views on disinfection, and which were so inti- 
 mately associated with " organic germs," I conclude 
 that he must have had very good grounds for this 
 public recantation. Since that period the eminent 
 physicist before alluded to has remained silent; his 
 reasoning, however, on the question at issue namely, 
 that in the main " the germ theory is the right and true 
 theory of infectious and contagious diseases" he attempts 
 to establish by the following argument, which may be 
 put syllogistically : Putrefaction of blood, or pus, is 
 disease ; the cause of putrefaction is animalcules or 
 their germs ; therefore, animalcules, or their germs, are 
 
IV. INTRODUCTION. 
 
 the cause of disease, and the germ theory of disease is 
 the true one. It will not be denied that Professor 
 Tyndall's experiments on dust have no bearing on any 
 of the members of the above syllogism, except the 
 second or minor premise, namely, the cause of putre- 
 faction is animalcules or their germs. But, whatever 
 may be their importance in that connection, it is evi- 
 dent that unless the major premise be sound, all the 
 rest is a baseless fabric. Now, in my humble opinion, 
 the latter is utterly unsound. The steps by means of 
 which pus and blood putrefy whether initiated by, 
 and exclusively due to, the presence of animalcules 
 derived from without, according to the Panspermists ; 
 or, on the other hand, according to the Heterogenists, 
 only accelerated by infusorial organisms, which are 
 themselves derived from the elements of putrescent 
 matter is riot a morbid process, nor even one proper 
 to living bodies, but a normal result of the operation of 
 the laws which regulate the breaking up of organised 
 matter. Some of the products of this process, under 
 certain circumstances, are, undoubtedly, capable of in- 
 ducing morbid action, but the process itself is not 
 disease. Grant putrefaction to be satisfactorily ex- 
 plained by the invasion of animalcules, or their germs, 
 and little or no light would thereby be thrown on the 
 intimate nature of disease ; for although certain morbid 
 processes have, with reason, been compared to putre- 
 factive fermentation, they cannot be admitted to be 
 identical therewith. 
 
 Professor Tyndall's argument, also, in favour of the 
 cause of putrefaction being animalcules, or their germs, 
 is equally fallacious. It runs thus : Whereas the outer 
 air (supposed to be always charged with germs capable 
 of inducing putrefaction), entering the pleural cavity by 
 an external wound and there commingling with blood, 
 is liable to cause putrefaction ; air from the lungs, when 
 it meets inside the pleura, with blood coining from an 
 
INTRODUCTION. V. 
 
 internal wound, caused say by the spike of a broken 
 rib, does not give rise to putrefaction; but the air, 
 which passes through the lungs in respiration, is known 
 to be deprived, by a kind of filtration, of the particles 
 of solid matter suspended in it ; therefore the difference 
 of the results in these two cases must be due to the 
 filtering out by the lungs of the supposed germs from 
 the air in the latter. If all the other conditions, under 
 which exist these two airs, were the same, it would, no 
 doubt, be logical to argue that the absence, or presence, 
 in them of solid particles of some sort (not necessarily 
 living germs, however) was the cause of the difference 
 in question. But so far from this being the case, both 
 air and blood, as they exist in the minute pulmonary 
 air vesicles and blood vessels, are under conditions 
 totally distinct from those that would affect the air and 
 blood which might meet in the pleura! cavity from an 
 external wound. In the matters of temperature, pres- 
 sure, and perhaps electricity, the conditions are entirely 
 dissimilar. The lungs, moreover, cannot be constantly 
 filtering out from the inspired air, and retaining 
 " germs/' without becoming largely charged with these 
 bodies. This being so, the blood which is sometimes 
 exuded into the air passages in lung disease, or at other 
 times is discharged therein from a ruptured vessel, 
 coming in contact with so great an accumulation of 
 septic germs, ought to be particularly liable to putre- 
 faction. But this is not the case ; nothing the least like 
 it has ever been observed. 
 
 Dr. Bastian, after due consideration, is clearly of 
 opinion that the "physico-chemical theory" explains both 
 fermentative and zymotic processes, and necessarily putre- 
 factive changes. His words are : *' I would maintain 
 that facts already known abundantly suffice to displace 
 the narrow and exclusively vital (germ) theory, and to 
 re-establish a broader physico-chemical theory of fer- 
 mentation. Whether the ferment in any given case be 
 
VI. INTRODUCTION. 
 
 an independent living organism ("organic germ"), a 
 fragment of non-living organic matter, or some mere 
 physico-chemical influence, as in the case of the action 
 of finely divided platinum, the indicative change is in 
 each case a result of chemical action. And similarly 
 with regard to "contagium," whether it be an inde- 
 pendent living organism, an altered though living tissue 
 element, a fragment of dead organic matter, a chemical 
 compound, or even the more vague influence of a " set 
 of conditions " which suffices to generate contagium de 
 novo, we have in each case to do with gradually initiated 
 chemical changes, destructive in kind and gradually ter- 
 minating in one or other of the recognised varieties of 
 zymotic affections. The changes in each case, even 
 when we have to do with living ferments or living con- 
 tagia (bacteria or fungi), would be due only to an infini- 
 tesimal extent to the organic multiplication of such 
 units, though the decompositions and chemical changes 
 set up by them in their respective fluids may be such as 
 to lead to the formation of a continuous set of inde- 
 pendent organisms." 
 
 The relationship existing between zymosis and the 
 modified processes of fermentation taking place in fruits 
 and tubers seems, indeed, far more close than that be- 
 tween the zymotic processes in animals and the ordinary 
 kinds of fermentation or putrefaction occurring in or- 
 ganic fluids. In processes occurring in vegetable tissues, 
 as well as in those morbid phenomena met with in 
 animals, the presence of rapidly multiplying independent 
 organisms is an occasional rather than a necessary 
 feature. Though usually absent in other allied pro- 
 cesses, organisms invariably manifest themselves through- 
 out the tissues of the beetroot and of the potato, when 
 these are placed under certain abnormal (unhygienic) 
 conditions. Very many illustrations can be adduced 
 which favour these views. " It is a well-established 
 fact that one of the most fatal diseases known to occur 
 
INTRODUCTION. Vll. 
 
 in silkworms (muscardine) can be generated de novo. 
 This fatal disease a disease in which fungoid elements 
 are found in the blood and growing through the various 
 tissues of the body elements, too, not at all dissimilar 
 to some of the elements met with in ovine smallpox 
 may be produced quite easily by shutting the silkworms 
 up in a glass-bottle or box, and by overfeeding them 
 for a time. Under these conditions their blood soon 
 swarms with characteristic organisms, and the fungus 
 grows through all the tissues of the body. When thus 
 affected, the animal is capable of spreading the disease 
 to other silkworms with which it may be brought into 
 contact ; for it is an eminently contagious disease, and 
 if we look at sheep-pox itself, the facts at present known 
 are surely irreconcilable with the notion that the or- 
 ganisms formed in the diseased tissues are themselves 
 the cause of the disease. After the first local contact 
 of the contagium with some surface, it is subsequently 
 supposed to multiply and be disseminated through the 
 body by means of the blood. But, on the other hand, it is 
 a well-attested fact that inoculation with the blood of 
 an animal suffering from ovine small-pox does not pro- 
 duce the disease in another animal. How can those 
 who believe in the germ theory for ovine small-pox 
 account for this absence of germs from the blood ? " 
 
 With regard to cholera, Dr. Lewis and Dr. Cunning- 
 ham, who have been engaged in a special inquiry into 
 the nature and causes of this disease, are of opinion 
 that it is not contagious ; that it is infectious seems also 
 doubtful; and the results at which they have arrived 
 is apparently that the prevalence of the disease is 
 intimately connected with meteorological phenomena 
 (chemico-physical), though of the nature of the con- 
 nexion nothing at present is known. Dr. Cunningham, 
 moreover, is convinced that cholera is due to certain 
 conditions of air and soil which are as yet but little 
 understood. 
 
Vlll. INTRODUCTION. 
 
 " With these facts before us," observes Dr. Bastian, 
 " we are asked to believe in a germ theory of disease, 
 because the phenomena of specific fevers are supposed 
 to be alone capable of explanation by reference to the 
 multiplication of hypothetical organisms within the body. 
 But, as Dr. Murchison has said, ' it seems that the facts 
 in question are equally capable of being explained 
 in other ways.' The same may be said of so-called 
 parasitic diseases of the skin, and the practical outcome 
 of the recent discussion is that, tying ourselves down 
 to no exclusive theories, we are taught, whilst excepting 
 the facts of contagion, not to be pure contagionists, but 
 rather to look abroad and around us, and seek for the 
 conditions of origin of contagious diseases. The ravages 
 of typhus in our crowded cities and in our gaols have 
 been enormously curtailed, not so much because of its 
 diminished spread by contagion, but rather because we 
 have learned what are the causes which engender it, 
 and are therefore better able to prevent its occurrence." 
 Discussion on the Germ Theory of Disease, Pathological 
 Society's Transactions, Vol. xxvi, 1875. 
 
ERRATA. 
 
 Page 3, last line in table of diseases for " Chlosma " read Chloasma. 
 
 7, line 22 for " become absorbed," read degenerated. 
 
 10, line 7 for " dermis," read derma. 
 
 18 append to last paragraph quoted, the name of Pence Jones. 
 
 55, line 10 after " time," insert by. 
 
 68, line 6 for " eyes water," read eye-waters. 
 
 72, line 6 -omit "a" before "fungoid;" and in line 7 for 
 
 " growth " read growths. 
 
 101, line 19 after " this," insert material; line 20 after "lungs," 
 
 insert which when; line 21 -after " salts," insert becomes 
 effete matter. 
 
 103, line 10 for "his," read Professor Tyndall; line 13 for 
 
 '* they," read germs. 
 
 104, line 23 -for * That," read A; and after " of," read fungus, 
 
 striking out the words, ' disease in which fungus bodies 
 are found." 
 
CONTENTS. 
 
 PAGE. 
 
 Introductory remarks on the aim of modern medicine ; the rise 
 and progress of a Vegetable Parasitic Theory of Disease ... 1 3 
 
 Table of skin diseases of a supposed parasitic origin 3 
 
 Class of diseases investigated at Mr. Hunt's Dispensary ... 5 
 
 Willan's classification of skin diseases 6 
 
 Organisation of the human body ; the influence exercised by 
 
 clothing, bath, &c., on health of body 69 
 
 Structure of the skin, the hair, nails, &c., and the changes 
 
 produced by disease 919 
 
 Hunt's tabular view of the morbific influences originating cuta- 
 neous disease 20 
 
 Parasitic diseases : atmospherical conditions necessary for 
 
 their production 21, 22 
 
 Trapping fungi and other floating atoms, by Lord S. Godolphin 
 
 Osborne 22 
 
 Botanical description of fungi and yeast-plant ; Liebig's in- 
 vestigations on fermentation ; the development of bacteria, 
 
 and conversion of yeast into sugar 23 26 
 
 Simplicity of structure of fungi and mildews ; ravages occa- 
 sioned by them in the vegetable and animal kingdoms ; 
 
 mode of destruction explained 2731 
 
 Various opinions on the nature of parasitic diseases of the skin 31 34 
 Description of the several diseases selected for microscopical 
 examination ; Porrigo favosa, favus, achorion Schonleinii... 35 40 
 
 Fermentation experiments with favus crusts 4044 
 
 Porrigo scutulata : ringworm ; description of disease, and 
 
 treatment; cases examined under the microscope 45 47 
 
 Porrigo decalvans : alopecia ; microsporon Audouini ; descrip- 
 tion of disease, cases examined under microscope 4750 
 
 Sycosis menti : mentagra ; microsporon mentagrophytes ; des- 
 cription of disease, treatment, microscopical examination of 
 
 Crusts 5052 
 
 Pityriasis versicolor : chloasma ; microsporon furfur; descrip- 
 tion of disease, treatment, microscopical examinations of 
 
 fungus 52, 53 
 
 Psoriasis : dry-tetter ; description of disease, examination of 
 
 fungus 54 
 
 Lepra vulgaris : microscopical examination of fungus 55 
 
 Eczema : running-scall ; description of disease. Erasmus 
 Wilson on the treatment of. Microscopical examination... 5658 
 
Xll. CONTENTS. 
 
 Impetigo : running-tetter ; description of disease, treatment, 
 fungus found in 58 -60 
 
 Herpes: dry-tetter 61 
 
 Ichthyosis: fish-skin 61 
 
 Vitiligo : veal-skin 61 
 
 Lichen : summer-rash ; description of disease and microsco- 
 pical appearance of scales 62 
 
 Lupus: the Wolf; description of disease, microscopical ex- 
 amination ; Mr. Hunt's treatment ; in what respect lupus 
 differs from leprosy 6365 
 
 Tinea tarsi: Ophthalmia tarsi; blear-eye; description of 
 
 disease, treatment, and microscopical appearances 66, 67 
 
 Ophthalmia, pustular conjunctivitis ; description of disease, 
 overcrowding as a cause in Government pauper schools and 
 school hospitals ; treatment 6771 
 
 Diphtheritic ophthalmia : description of disease, microscopical 
 
 examination of, with an illustration 72 75 
 
 Spilus 76 
 
 Molluscum 76 
 
 Mycetoma : Fungus-foot disease of India ; Dr. Carter's des- 
 cription of; Rev. Mr. Berkeley's opinion of; Dr. Blanc's 
 case; appearances under high powers of the microscope ... 7789 
 
 Conclusion arrived at after a survey of parasitic diseases of 
 the skin 89, 90 
 
 A fungoid, or organic germ theory of cholera. The vital 
 germ, and physical theories of disease explained. Dr. 
 Tytler's supposed discovery of the cause of cholera ; Drs. 
 Wallace, Mitchell, and other authors' fungoid theories ; 
 Professor Hallier's micrococci, or cholera contagium ; Dr. 
 Thudichum's experiments on mice ; Drs. Lewis and Cun- 
 ningham's investigations on the blood of cholera patients, 
 bacteria not discovered 90 99 
 
 Dust and Disease : Dr. Angus Smith's investigations of the 
 air of towns ; the air we breathe ; cotton-wool respirators ; 
 Professor Tomlinson's mode of keeping out dust and pre- 
 venting crystalisation ; the effects of dust on the lungs of 
 miners 100102 
 
 The microscope in the detection of dust in the atmosphere, the 
 determination of the relative proportions of organic matter 
 in air, and the difficulty of reconciling it with a germ theory 
 of cholera 103106 
 
 Aphthae, or thrush ; description of disease, and its supposed 
 fungoid origin 106, 107 
 
 The influences exercised by organic particles on the health of 
 individuals : a formula for cholera 107,108 
 
SKIN DISEASES 
 
 OF A 
 
 SUPPOSED PAEASITIC OBIGIK 
 
 In organized nature everything is minute, nothing can be done by 
 rapid generalizations of aspiring genius, which makes use of no instru- 
 ments but words. But all things are effected by laborious, patient 
 investigation, by the mechanical but important material apparatus of 
 hands and eyes." Sir Humphrey Davy. 
 
 THE aim of modern medicine seems to be directed, 
 much more than formerly, towards making distinctions 
 where none, when properly examined, are perceptible. 
 This is not only embarrassing to the student in medi- 
 cine, but is quite opposed to the views of physiologists 
 who are strong in their conviction that all varieties 
 should be reduced to uniformity. 
 
 The charge brought against modern medical practice 
 in general is especially exemplified in the study of 
 diseases of the skin ; for it seems that certain derma- 
 tologists of repute have thought it right to split them 
 up into endless varieties ; thus determining this class of 
 affections from the ordinary course, and apparently for 
 no better reason than that of making it appear that 
 cutaneous diseases are not to be treated upon those 
 principles which guide us in the treatment of disease 
 generally. It is therefore by no means surprising that 
 the relation skin affections bear to pathology should 
 have been very nearly overlooked in an anxiety to 
 establish wide distinctions and over nice classifications. 
 
2 SKIN DISEASES OF A 
 
 The source which has hitherto furnished us with the 
 indispensable elements for the study of this branch of 
 medicine has also served, to perpetuate erroneous views 
 as to the nature of the diseases themselves; conse- 
 quently an irrational empiricism as regards their treat- 
 ment has taken the place of reasoning and ripened expe- 
 rience. The subject indeed has been too long abandoned 
 to the specialised proclivities of the day, and it has 
 therefore become almost a distinct branch of medicine 
 having but little connexion with any other. The sound 
 practitioner knows full well that the majority of cuta- 
 neous affections are symptomatic of other diseases ; the 
 outward manifestations, as it were, of some internal 
 affection, or an accompanying symptom of a deterio- 
 rated state of health. I have made attempts to enforce 
 these views upon the profession, but I fear without 
 having accomplished all I could wish ; my remarks have 
 a special reference to the German theory of the vege- 
 tablfe origin of certain skin diseases propounded by 
 linger in 1833. This tempting theory was not long in 
 attracting attention and finding supporters even among 
 men of eminence, as Schb'nlein of Berlin, Gruby, Robin, 
 Kuchenmeister, &c. ; and it derived some impetus from 
 the circumstance that Professor Owen attributed the 
 death of a Flamingo* to the ravages of a fungus found 
 in the lungs of the bird. Not long afterwards, Bassi of 
 Lodi demonstrated the vegetable character of a disease 
 
 * Owen, while dissecting a Flamingo, found the lungs filled with 
 tubercles and vomicse. "I was much struck," he writes, "with 
 finding the inner surface of the latter cavities, and that of most of the 
 smaller ramifications of the bronchial tubes, covered over with a green 
 vegetable mould, or rnucor. As the individual was examined within 
 twenty-four hours after its death, it seemed reasonable to conclude 
 this mucor had grown there during the lifetime of the animal. Thus 
 it would appear that internal parasites are not exclusively derived 
 from the animal kingdom, but that there are Entophyta as well as 
 Entozoa" Zoological Society's Proceedings, Aug. 28, 1832. 
 
SUPPOSED PARASITIC ORIGIN. 
 
 3 
 
 which caused great devastation among silkworms. M. 
 Gruby subsequently announced the fungoid character of 
 mentagra or sycosis; while numerous other observers 
 attempted to identify several species of fungi with the 
 diseases which they believed were produced by them. In 
 this way it has come about that several of the most 
 common skin affections have been separated and de- 
 tached from the rest, and are now almost exclusively 
 regarded as of a fungoid or parasitic origin. Thus, the 
 parasite supposed to be peculiar to, and productive of, 
 each disease, has been minutely described, and honoured 
 with a name derived from the name of the disease which 
 it is supposed to have originated, as appears in the fol- 
 lowing table : 
 
 WlLLAN. 
 
 BAZIN. 
 
 WILSON. 
 
 PARASITE, 
 
 Porrigo favosa and 
 
 Tinea favosa 
 
 Favus 
 
 Achorion Schonleinii 
 
 lupinosa 
 
 
 
 
 Porrigo scutulata 
 
 Tinea tonsu- 
 
 Trichoses fur- 
 
 Trichophyton tonsu- 
 
 
 rans 
 
 furacea 
 
 rans 
 
 Porrigo decalvans 
 
 Tinea decla- 
 
 Alopecia 
 
 MicrosporonAudouini 
 
 
 vans 
 
 
 
 Mentagra 
 
 Tinea sycosa 
 
 Sycosis 
 
 Microsporon menta- 
 
 
 
 
 graophytes 
 
 Pityriasis versicolor 
 
 Pitiriasis 
 
 Chlosma 
 
 M icrosporon furfur 
 
 Now, this seductive theory not only involves, as I 
 have intimated, an important principle of pathology, 
 but it places the parasitic fungi above described in 
 a category by themselves, and invests them with charac- 
 teristics entirely at variance with those of the natural 
 history of the family of fungi, whose leading feature 
 appears to be that of selecting diseased and decayed 
 structure as the soil most essential to their existence ; 
 whereas this hypothesis assigns to them healthy organ- 
 ized matter to live and prey upon, thereby establish- 
 ing a specific disease. In examining into the truth or 
 
 B2 
 
4 SKIN DISEASES OF A 
 
 fallacy of this theory by the light of physiology, we 
 must bear in mind that the surface of the human body 
 is supplied with a delicate covering, one office of which 
 is to excrete, and another to eliminate or exude, effete 
 matter from the blood. The excretion consists chiefly 
 of epithelial scales, and the exudation is mostly made 
 up of fluid and gaseous matters, which sometimes 
 become condensed and dried on the surface of the 
 epidermis. The epithelial scales are friable and separ- 
 able by very slight friction during health, and the 
 transpired fluid makes its escape, under ordinary cir- 
 cumstances, without any assistance from without. But 
 want of cleanliness, deficient exercise, and more fre- 
 quently a deranged state of the health, especially a 
 vitiated condition of the body, interferes with the natural 
 processes of elimination; and then the skin itself 
 becomes diseased, and in this diseased condition may 
 become infested by parasitic fungi, the spores and fila- 
 mentous threads of which find a nidus in an abraded 
 portion of the cuticle, the shafts and roots of the hairs 
 are invaded, the hairs become brittle and stunted in 
 growth, and at length perish and fall off. 
 
 While admitting the existence of certain parasitic 
 fungi in connection with favus, porrigo, &c., it is suffi- 
 ciently evident, after a careful study of the writings of 
 Gruby, Bennett, and others, that they must be looked 
 upon as a result, and not as a cause of disease ; and it 
 is important to remember that parasites are not even 
 universally present in these affections. In the year 
 1856, I undertook, at the instigation of my friend, Mr. 
 Hunt, an investigation into the nature and origin of the 
 so-called parasitic diseases of the skin; and, without 
 having formed any preconceived opinion upon the sub- 
 ject, and for the elucidation of particular points, I made 
 in all a very large number of examinations of the pro- 
 ducts of cutaneous affections. The cases investigated 
 
SUPPOSED PARASITIC ORIGIN. 5 
 
 were chiefly derived from fourteen genera of Willan's 
 classification; namely, Porrigo, Psoriasis, Pityriasis, 
 Sycosis, Lepra, Lupus, Lichen, Impetigo, Furunculus, 
 Eczema, Yitiligo, Spilus, Ichthyosis, and Acne. The 
 spores or filaments of a cryptogamic plant w$re found 
 in most of the genera. In four of the several diseases 
 arranged under the heading of 1st, Porrigo decalvans, 
 Tinea decalvans, or Alopecia circumscripta ; 2nd, Porrigo 
 scutulata, Tinea tonsurans, or Herpes tonsurans ; 3rd, Pity- 
 riasis versicolor, Pityriasis lutea, or Cloasma ; 4th, Sycosis, 
 or Mentagra in these special forms, previous observers 
 had described fungoid growths ; as also in Porrigo favosa ; 
 but in six or seven other well-known diseases Psoriasis, 
 Lepra, Lichen, Eczema (with or without Tinea tarsi), 
 Spilus, and Ichthyosis, no writer had noticed the pre- 
 sence of fungi ; and therefore they were always sepa- 
 rately described, and considered free from vegetations ; 
 and they have accordingly not been placed in the class 
 Dermatophyta, a name bestowed upon certain affections 
 of the skin supposed to be of parasitic origin. The 
 publication of my investigations in 1856, 57, and 58, 
 attracted some attention; and many other observers 
 took up the important question, and, upon a closer 
 examination of my facts, came to the conclusion that 
 diseases of the skin associated with vegetable growths 
 were not exclusively due to the parasite ; and although 
 the growth might aggravate the disease, its true patho- 
 logy was a degenerate condition of the blood, an arrest 
 of the function of the skin. 
 
 In my remarks upon cutaneous diseases, I have 
 adopted Willan's classification, as the simplest and best ; 
 for, in my opinion, old as it is, no modern arrangement 
 can at all compare with it, or appears to be likely to 
 displace it in the estimation of those who study skin 
 diseases. Dr. Willan arranged affections of the skin 
 under eight orders ; that is, according to certain external 
 
6 SKIN DISEASES OF A 
 
 indications presented by the primary outbreak of the 
 disease. These orders are as follows : 
 
 Order 1. Papulae (pimples). 
 
 2. SquamaB (scales). 
 
 3. Exanthema (rashes). 
 
 4. Bulla3 (blisters). 
 
 5. Pustulee (pustules). 
 
 6. Vesiculse (vesicles). 
 
 7. Tuberculse (tubercles). 
 
 8. Maculae (spots). 
 
 This appears to be a rational classification, and one 
 by means of which we are enabled to generalize skin 
 affections, and submit them to an examination perfectly 
 in accord with the pathology of the day. 
 
 Before I venture to speculate upon pathological 
 changes, say what is the normal condition and what is 
 a departure from the healthy state, whether of the cuta- 
 neous surface, or of the more deeper seated parts of the 
 body, it is quite necessary that I should offer a few brief 
 remarks on the minute anatomy, structural arrange- 
 ment, and functions of the several parts with which I 
 am about to deal. The literature of this part of the 
 subject has grown enormously of late years, and there- 
 fore it is difficult to compress into a few terse sentences 
 all that should be written on many points of value and 
 interest. The physiological relation which the skin 
 bears to the rest of the body, and to its healthy con- 
 dition, is indeed a matter of considerable importance, 
 especially as the state of the health in a great measure 
 depends upon certain subsidiary functions which it is 
 designed the cutaneous surface should assist in the per- 
 formance of; namely, absorption, secretion, excretion, 
 &c. 
 
 In every case, it must be remembered that, whether 
 attention be given to the organisation of the animal or 
 
SUPPOSED PARASITIC ORIGIN. 7 
 
 vegetable kingdoms, a great similarity will appear in 
 the mode of growth and repair going on, and contri- 
 buting to, the increase of the several parts of the indi- 
 vidual. Additions and repairs are made from within 
 and extending outwards ; each point or limb grows, or 
 is added to, by an interstitial deposit of germinal 
 matter, and not by the aggregation of particles exter- 
 nally brought into contact with the surface. In the 
 animal body, much depends upon the perfection of its 
 several parts, and nothing can long remain stagnant 
 or out of health without endangering the safety of the 
 fabric. 
 
 In man, who stands at the head of organised beings, 
 are tissues differing greatly in constituency and density ; 
 from the fluids of the eye and the more consistent fatty 
 matters beneath the skin, to the resisting muscles and 
 denser bone ; from the soft and fragile skin covering the 
 body to the flinty enamel of the teeth; alike derived 
 from cells. The same law of growth holds good with 
 regard to all, whether fluids or solids ; they constantly 
 require renewing ; the older particles, cells, entering into 
 the several tissues, become absorbed or worn out, and 
 thrown off from the body as effete matter ; while new 
 particles are or must be as rapidly formed to supply 
 their place. Life, in short, is sustained by a constant 
 abstraction of certain elements from the external world; 
 whilst decay and death is a result produced by the using 
 up of the same, and their return in one form or another 
 to the source whence they were originally derived. Life 
 is inseparably linked with change, the arrest of which is 
 temporary death : nevertheless, it is only through inces- 
 sant destruction and reconstruction that vital pheno- 
 mona emerge an ebb and flow of being. 
 
 " The ordinary oxidation that takes place in each tex- 
 ture of the body gives heat and motion sufficient to 
 carry on the ordinary nutrition of the structure ; but 
 
8 SKIN DISEASES OF A 
 
 the smallest increase of oxidation, set up by direct extra- 
 vascular or indirect intra-vascular motion through the 
 nerves, is followed by altered heat, motion, and nutri- 
 tion. The effect of slow but continued per-oxidation 
 may be constantly watched in the skin of the eye. The 
 slightest long-continued mechanical pressure pro- 
 duces not only thickened cuticle, but altered nutrition 
 of the skin itself. In the cornea, a chronic inflammation 
 from some very slight mechanical cause will leave a 
 thickening which may be perceptible for years." 
 (B. Jones.) 
 
 Unless a due amount of animal heat were main- 
 tained, it would be impossible to carry on the several 
 functions of life, most of which are either impaired 
 or altogether arrested by a very low temperature. Man 
 is so constituted as to be able to resist the effects of 
 considerable changes of temperature; nevertheless, nature 
 has left him the least protected, physically considered, 
 of any animal ; his skin, being without external cover- 
 ing, demands on this account more care and attention. 
 From this circumstance alone, the cutaneous surface is 
 subject to frequent derangements. The sensible and 
 insensible perspiration, breathing in fact, which is car- 
 ried on through the skin, is of the highest importance 
 to health, nay, even to life. If we cover the whole of the 
 skin with an impermeable varnish, or enclose the greater 
 part of the body in an air-tight case, the individual so 
 treated dies in a few hours. The escape of the heat of 
 the body through the skin takes place quite indepen- 
 dently of the exhalation of the gaseous vapour ; although 
 this, together with the fluid perspiration, is, under ordi- 
 nary circumstances, quite sufficient to regulate the tem- 
 perature of the body. The use of artificial clothing, in 
 regulating the temperature, acts by moderating and 
 restraining the escape of caloric from the body ; the 
 warmer descriptions of clothing preventing the escape 
 
SUPPOSED PARASITIC ORIGIN. 
 
 of heat, the lighter favouring this ; and it is upon this 
 principle alone that articles of clothing appear to be 
 warm or cold. I will merely add that the power pos- 
 sessed hy the skin of controlling the excess of the 
 temperature of the human body is manifest in hot sea- 
 sons and in tropical climates, when, although the heat 
 may reach several degrees beyond the temperature of 
 the blood, it exerts no influence over the usual standard 
 of the body, 97 deg. Farht. This power is still more 
 manifest in the use of the Turkish bath, heated to 200 
 deg. or more, and which is borne by those accustomed 
 to its use with a sense of comfort. The excess of heat 
 is carried off by the increased secretion of the cuta- 
 neous perspiration, which absorbs the caloric in the 
 formation of watery vapour, and is thus discharged from 
 the body. 
 
 In many, if not in most diseases, the functions of 
 the skin exercise a most important influence ; too 
 little regard is paid to this and the consequent advan- 
 tanges to be obtained in their treatment by promoting 
 its healthy action. It will be sufficient for my purpose 
 at present if I enumerate the several functions of the 
 skin, and which are fivefold, namely : secretion or 
 exudation, absorption, sense, sensibility, and as a store- 
 house of animal heat to sustain the temperature of the 
 body. The several functions will be noticed somewhat 
 more in detail in connection with the minute anatomy 
 of the cutaneous covering. 
 
 THE ANATOMICAL STRUCTURE OF THE SKIN. 
 
 The skin is composed of three layers, the epidermis, 
 or cuticle, the dermis or true skin, and the subcutaneous 
 cellular tissue. It is largely supplied with blood vessels, 
 nerves, glands, and adipose tissue. Muscular fibres are 
 found in the superficial layer of the dermis in close 
 
10 SKIN DISEASES OF A 
 
 connection with the hairs of the body. In some of the 
 lower animals, as the cat tribe, mouse, &c. these muscles 
 are arranged in bands about the nose, and they serve 
 to erect the hairs and convert them into sensitive tactile 
 organs. 
 
 Commencing with the deepest layer, and the most 
 important, the dermis or corium as it is sometimes called, 
 is not a plain surface, it exhibits elevations, with cor- 
 responding depressions almost throughout. The upper- 
 most layer assumes the appearance of numerous conical 
 eminences or vascular loops termed papillae. The 
 fat, adipose, and connective tissues, are situated in this 
 layer; but where the skin is loose, or can be thrown 
 into folds, as about the eyelids and over the joints, no 
 fat is stored. No papillae exist where the skin is fur- 
 rowed, as in the palm of the hands, &c. ; but they are 
 very freely distributed to semi-moist parts, as the lips, 
 gums, mouth, &c. ; and to such parts they give a soft, 
 smooth appearance. The sudoriferous glands are si- 
 tuated in this layer ; they are small oval bodies with 
 spiral tubes running up through the several layers of 
 skin to the surface. The sweat-glands are very impor- 
 tant, and it is computed that there are 3,528 in every 
 square inch of the hand. The secretion from these 
 glands constitutes the sensible and insensible perspira- 
 tion ; the former is that which appears on the sur- 
 face, where it rests for a time and then drops off; the 
 latter is that which passes off insensibly, or without 
 notice, in the form of watery vapour. The average 
 quantity excreted from the body in the twenty-four 
 hours is estimated at from two and a half to five pounds : 
 this of course varies with the temperature, time of 
 year, &c. It is one of the most watery fluids of the 
 body, leaving only about one per cent, of solid matter 
 after evaporation. The perspiration contains sodium 
 chloride, ammonium phosphates, and other organic 
 
SUPPOSED PARASITIC ORIGIN. 11 
 
 matters, largely mixed with epithelium scales and fatty 
 matters, which impart at times a remarkably sour smell 
 to the body. 
 
 The epidermis or cuticle, the outermost layer of 
 the skin, is composed of several layers of flattened- 
 out scales. It was thought that no well-defined limit 
 existed between the dermis and epidermis, but this is 
 only true during the earliest stages of existence. In 
 very young children, the two structures are invariably 
 continuous with each other ; the most superficial portion 
 of the derinis consisting of a homogeneous layer of 
 plastic material, protoplasm, and fine granular matter. 
 The mucous layer, rete Malpighii, is composed of gra- 
 nules that are enlarged or enlarging by the absorp- 
 tion of a definite proportion of the protoplasmic mass. 
 These scales or cells, as they come nearer the surface 
 layer, assume a flattened-out form, and are somewhat 
 horny in character. This change appears to commence 
 with a shrinking of the internal body, nucleus, which 
 divides into spaces, vacuoles. Besides these cells there 
 are others in the mucous layer that resemble the con- 
 nective tissue cells of the dermis ; these are small in 
 size, and of a fusiform shape, each having in its interior 
 one or more nuclei. This layer of cells no doubt plays 
 an important part in cutaneous affections. The scales 
 of the epidermis are incessantly thrown off from the 
 surface of the body ; and, should the process be in any 
 way impeded or arrested, derangement of health or 
 disease will assuredly follow. The fat tissue of the skin 
 is necessarily an important structure ; and although each 
 fat-cell contains but a single globule of oily matter, it 
 requires a complete network of capillary blood vessels 
 to maintain and renew the supply. The fat-glands, 
 although present in almost all parts of the body, are 
 more numerous in those covered with hair ; they are, 
 however, entirely absent in the palms of the hand and 
 soles of the feet. 
 
12 SKIN DISEASES OF A 
 
 The papillae, or vascular loops, have medullary 
 nerve fibres running into them, and which afterwards 
 pass to the tactile corpuscles. The lymphatics of the 
 skin are accompanied by one or two blood vessels 
 throughout their whole course. I may here observe of 
 the glandular structure situated in the eyelids, that it 
 is more complex than the rest ; the gland ducts there 
 ramify about in all directions, for the purpose of pre- 
 serving the healthy nature of the secretion that nourishes 
 the hairs about the eyelids. Should these glands become 
 inflamed, the ducts are obstructed, and a disease is pro- 
 duced, tinea tarsi, common enough among a certain 
 class of people. This disease of the lids is accompanied 
 by the formation of small pustules and scabs, and leads 
 to destruction, falling out of the eyelashes. 
 
 In the Malpighian layer of the epidermis, the first 
 series of cells is described as columnar in form, while the 
 immediately superimposed layer is cubical in form, of a 
 larger size, with a granular nucleus, in which nucleoli 
 are visible. The superficial or horny layer of the 
 epidermis is composed of flat polygonal tesselated scales, 
 the nuclei of which have nearly disappeared. The colour 
 of the skin, noticed in certain persons, and the deep 
 brown of the negro, depends on the presence of coloured 
 granules contained in the cells of the Malpighian layer. 
 In addition to the nervous supply already mentioned, 
 preparations of the skin, made by staining with a solu- 
 tion of the chloride of gold, demonstrate the presence 
 of an abundant supply of non-medullary nerves, ending 
 in free extremities, and which run between the cells of 
 the mucous layer. The subcutaneous nerve trunks are 
 made up of both medullary and non-medullary nerve 
 fibres; these dip down into the deeper parts of the 
 dermis, and there divide and sub-divide into several 
 branches, for the purpose of accompanying the blood- 
 vessels. It is in this part of the skin that the Pacinian 
 
SUPPOSED PARASITIC ORIGIN. 13 
 
 bodies, tactile corpuscles, are found ; the finer nerves 
 seem to terminate in these bodies; this doubtless ex- 
 plains their extreme sensitiveness. The nervous struc- 
 ture is one of great interest and importance to the 
 Dermatologist. The sweat gland, as we have already 
 seen, is scarcely a less important appendage of the skin. 
 It usually presents a contorted knot-like body, with a 
 spiral-shaped tube making its way through the dermal, 
 the mucous, and epidermal layers. According to Krause, 
 there are 2,736 sweat glands in every square inch in the 
 palm of the hand, 2,685 on the sole of the foot, 1,490 
 on the back of the hand, 1,303 on the neck and fore- 
 head, 417 on the back and buttock. Those situated 
 under the armpits cannot be exactly compared, as 
 regards their number, with those of other parts of the 
 body ; but their size is very remarkable. Besides the 
 various structures enumerated, there are the muscles of 
 the skin, composed of both smooth and serrated fibres ; 
 the latter reach the skin from the deeper lying parts in 
 the face, the beard, and nose, while the former, or 
 smooth, are in immediate connection with the hair 
 follicles. Many hairs possess two muscles ; these split 
 up and pass over the nearest sebaceous gland, partly 
 encircling it. As the hairs are inserted obliquely in the 
 skin, forming a moderately acute angle with the surface, 
 and the muscular bundles lie in a plane of a correspond- 
 ing obtuse angle, the muscular contraction must ob- 
 viously cause the hair to become almost erect. The well 
 known effect of goose skin is in the same way produced 
 by muscular contraction. Beside the several layers 
 enumerated, there is a basement membrane which has 
 been always described as structureless, but by the aid of 
 reagents this is seen to be cellular. 
 
 The hairs are next in importance of the cutaneous 
 structures ; these may be briefly described as cylin- 
 drical modifications of the epidermis, peculiar outgrowths 
 
14 SKIN DISEASES OF A 
 
 of the epithelial scales, having a hardened, vitreous 
 or horny exterior. The hair scales overlap each other, 
 and are compactly held together by a layer of connective 
 tissue, that becomes firmer and more solidified when 
 brought into immediate contact with the outer air. A 
 hair consists of a root, a shaft, and a point. The 
 portion of the shaft situated beneath the skin pre- 
 sents a bulbous enlargement, and here it is surrounded 
 by a network of bloodvessels, nerves, fat, and sebaceous 
 matters, all of which are necessary to maintain it in a 
 healthy condition. The central portion of each hair is 
 filled with a medulla, and this, together with the pigment 
 granules contained in the outer cells, imparts the variety 
 of colouring observed in animals provided with a thick 
 hairy covering. 
 
 To be somewhat more precise in describing a hair, 
 we observe that it is composed of several layers of con- 
 nective tissue and epithelial cells ; this is better seen on 
 making a horizontal section of a small bundle of hairs, 
 and submitting them to a magnifying power of about two 
 hundred diameters. It is then noticed that the external 
 layer of each hair appears to be serrated; this arises 
 from the overlapping of the scales, one lying over the 
 other as tiles on the roof of a house. That portion of 
 the hair concealed beneath the skin, the root, is fixed in a 
 peculiar fold or sac, the hair-bulb. It is scarcely right to 
 call this part of the hair shaft bulbous, as the hair 
 often terminates in a blunt point. The hair follicles 
 vary a good deal in length ; those in connection with the 
 longest hairs as of the head and beard pass into 
 the subcutaneous tissue, while in other parts of the body 
 they extend only a very short distance. In every case a 
 small conical network of bloodvessels surrounds the 
 hair-bulb, and it is from this point that the growth of the 
 hair proceeds; and here the elements of the cortical sub- 
 stance changes into horny scales, the more recently 
 
SUPPOSED PARASITIC ORIGIN. 15 
 
 formed epithelium being the deepest. The hair is formed, 
 like the teeth, from a pulp enclosed in a follicle; 
 when a hair is plucked from its follicle, it is found that 
 the root-sheath adheres closely to it. The stem of the 
 hair possesses a certain power of growth; indeed so 
 highly organised is it, that it would be strange if it were 
 not so ; and this view receives confirmation in a disease 
 called Plica Polonicd. The hairs in this affection are 
 split up into fibres, and at a considerable distance from 
 their bulbs a glutinous substance exudes which mats 
 them together ; nevertheless, they continue to grow. 
 
 The colour of the hair is sometimes suddenly changed, 
 by some strong mental emotion, from black to white. One 
 of the most remarkable cases of the kind on record is that 
 of the Pere Lefevre, narrated in a recent trial.* The loss of 
 pigment or colouring matter in the cortex and medullary 
 substance produces grey hair ; but this does not destroy 
 its vitality. The permanent hairs increase to a certain 
 length ; and when the limit of growth is attained, the 
 papillae are no longer able to support their weight, and 
 they then fall out ; new hairs are, however, developed in 
 their place. In human beings, a succession of new hair is 
 continually taking place ; but in the lower animals there 
 is a periodical shedding and renewal of what forms an 
 outer warm coat. The falling off of the hair arises from 
 the circumstance that no new epithelial scales are 
 formed, or the last formed receive no nervous supply, 
 and are consequently drawn out into condensed elon- 
 gated hair cells ; while those shed during some deranged 
 
 * Pere Lefevre's account of this singular change, brought about in 
 a single night, is as follows : "I was in Spain when I heard the news 
 of the death of my father. In the night I dreamt that I saw him 
 killed before my eyes, and my emotion was so great that when I awoke 
 my hair had turned quite white." This is a notable example of the 
 influence exerted by the mind or nervous system on the health of the 
 body. 
 
16 SKIN DISEASES OF A 
 
 state of the health are either not replaced, or, when 
 replaced, the hairs are stunted and colourless. Baldness 
 frequently depends upon a double cause a diseased 
 condition of the bulbs and surrounding connective tissue. 
 In advanced age, loss of hair is no doubt the result of a 
 deficient blood supply, and is more frequently constitu- 
 tional than local. It has been observed again and again 
 that persons whose circulation is languid, slow, or 
 defective, become bald at a very early period of life. 
 The arrest of development, diseased condition, here 
 referred to, does not originate in structures beneath the 
 surface of the skin, and apparently far removed from 
 the attacks of vegetable parasitic growths. The fungi, 
 in exceptional instances, do appear to penetrate the 
 dermic structure. It has been discovered that a rare 
 form of fungoid disease occurs among the native popu- 
 lation of certain parts of India; but this is always 
 confined to a foot or a hand, and never attacks any other 
 part of the body. 
 
 I shall have occasion to revert to the fungus foot- 
 disease more in detail further on. I proceed to consider 
 the structural character of the nails. It is well known 
 that the nails form a horny and somewhat transparent 
 termination to the fingers and toes; they differ from 
 hairs, inasmuch as, although very dense outgrowths of the 
 epidermis, the epithelial cells spread out and array 
 themselves in an imbricated manner, one layer leaving 
 only a portion of the next uncovered, the last lying 
 embedded in a fold of the skin, and forming a matrix 
 beneath the surface. The nails, like the hairs, are com- 
 posed of epithelial scales, connective tissue, dermis, 
 and a mucous layer of the bed-matrix. The mound- 
 like elevations of the matrix form a series of from 
 fifty to ninety ridges, which are chiefly made up of 
 parallel fibres of connective tissue and fusiform cells. 
 The deepest layer of cells is columnar, and the blood- 
 
SUPPOSED PARASITIC ORIGIN. 17 
 
 vessels form a plexus, from which numerous vascular 
 loops are sent off to supply the papillae. The nerves 
 lie embedded in the subcutaneous tissue of the nail- 
 bed. Sections of nail, soaked in a potash solution for 
 a short time, easily break up into numerous fragments 
 well suited for an examination under a magnifying 
 power of 300 diameters. The dense mass is then seen 
 to be composed of numberless nucleated epidermic cells 
 cemented together by connective tissue and albumen. 
 When the nail-wall is deficient in structure, as fre- 
 quently occurs with the little toes, the nail does not 
 grow out, but, having increased in thickness and attained 
 to a certain height, it breaks off. Irritation of the 
 matrix, produced by pressure or other cause, is attended 
 by inflammation and suppuration, and loss of the nail. 
 New nail is formed by the matrix, so that this is a very 
 important part of the structure ; and even suppurative 
 inflammation occurring in the nail-bed will not stop the 
 growth of new nail. This fact constitutes another in- 
 stance of the almost entire dependence of the dermal 
 appendages upon the deeper-seated internal structures, 
 and quite independent of external causes. Late re- 
 searches prove that, in the earliest embryonic stage, the 
 formative processes and changes begin with a division 
 and splitting up of the same cells as those seen in the 
 adult. The small round cells increase and multiply, and 
 become transformed into various definite tissues, recog- 
 nisable as skin, hair, glands, &c. up to the wonderfully 
 perfect optical crystalline structure of the eye. These, 
 together with the epithelial membranes of the nose, 
 ear, &c. are all developed from one primary series of 
 cells, and the order of development in the normal 
 state never seems in any way to vary. This indicates 
 an intimate relationship between the organs of sight, 
 hearing, and the skin ; hence the constant liability of 
 these several parts to become simultaneously affected. 
 
18 SKIN DISEASES OF A 
 
 If this be so, how necessary it is to possess a perfect 
 knowledge of the microscopical anatomy of the skin, and of 
 the pathological processes which determine and maintain 
 the human frame in a healthy state ! 
 
 Who can rise from a study of the outer covering of 
 the body, and say that when abnormal changes are ob- 
 served in any part of it they belong to a distinct and 
 separate nosological order ? No one doubts that disease, 
 whether of the external or internal parts of the body, 
 must be considerably modified by the anatomical or struc- 
 tural arrangements in its own immediate locality. An 
 eruption taking place on the surface of the body is but a 
 manifestation of a pathological change in the organization 
 generally, modified by the structure in which it makes 
 itself apparent to the eye. It has been observed that 
 although the quantative and qualitative errors of the 
 chemical composition of the different structures of the 
 body attract and demand much attention, neverthe- 
 less little is known of the causes on which these errors 
 depend. "The excess or deficiency in the supply of 
 nutritive material the wrong quality and quantity of the 
 matter supplied the wrong chemistry, in the act of 
 assimilation in the different textures the excess or 
 deficiency of chemical action in the removal by the used 
 organs these constitute a multitude of diseases ; some 
 of which are known as hypertrophy, atrophy, and de- 
 generation ; and most of which are only guessed at even 
 at the present day." 
 
 As regards the pathological anatomy of the skin, it 
 is believed, and with a good show of truth, that the 
 varied forms of cutaneous affections are essentially of 
 an inflammatory type, differing among themselves in 
 intensity, and changing with the inflammation present and 
 the part affected. Take eczema as an example. In this 
 disease the papilla are the chief seat of the affection ; 
 and in the earliest stage of the disease these bodies 
 
SUPPOSED PARASITIC ORIGIN. 19 
 
 increase in size, and contribute towards the exudation 
 of a clear serous fluid. The connective tissue corpuscles 
 become stimulated in their growth by the abundance of 
 pabulum ; these enlarge and multiply, and the resultant 
 free cells migrate from the papilla and insinuate them- 
 selves between those of the mucous layer. Such cells pre- 
 sent an elongated form, branch out towards the corneal 
 layer of the epidermis,and there unite to form an irregular 
 network with those of the mucous layer. Some ana- 
 tomists look upon these especial cells as constituting a 
 system of nutritive canals for the mucous-layer ; and 
 by their agency a larger quantity of serous fluid 
 infiltrates the papilla, and is brought to the tissue, thus 
 causing it to swell out even to bursting. The epidermis, 
 in a somewhat similar manner, from irritation becomes 
 separated as a minute blister, bursts, and ends in a 
 running sore. It is further supposed that even pus 
 cells, or pustules, filled with a serous fluid, do not 
 proceed from the multiplication of the cells of the rete 
 mucosum, or mucous layer, but are rather offsets from the 
 spindle-shaped cells of the connective tissue and papilla, 
 which, multiplying very rapidly, are forced to the 
 surface. 
 
 Although it may appear that I have entered some- 
 what minutely into the anatomical and pathological 
 relations of the skin, I believe it will be conceded, by those 
 acquainted with the subject, that no one can cope satis- 
 factorily with its morbid lesions unless he possess a 
 perfect knowledge of the several parts with which he 
 has to deal ; neither is it possible to distinguish one 
 disease from another without an acquaintance with 
 secondary results. For this reason, it is often necessary to 
 proceed by another and very generally adopted method ; 
 namely, by comparing the special characters of one form 
 of disease with that of another, and by a process of 
 elimination, arrive ultimately at a correct diagnosis. 
 
20 
 
 SKIN DISEASES OF A 
 
 If, for instance, the epidermis or cuticle presents a simple 
 elevation with a clear transparent fluid, it may be safely 
 inferred that the disease is neither an exanthera nor a 
 variola. By another method we obtain a knowledge of 
 the secondary products which form the basis of Willan's 
 classification; and this may enable us to distinguish 
 varieties as an eczema from a herpes. 
 
 A simple view of the causes and morbific influences 
 at work in the production of skin diseases, in almost 
 every form of eruption, is exhibited in an intelligible 
 tabular form by Mr. Hunt.* The only diseases men- 
 
 * Tabular View of the Morbific Influences originating Cutaneous Diseases* 
 
 1. EPHEMERAL INFLUENCES. 
 produce 
 
 2. 
 
 PERSISTENT INFLUENCES. 
 produce 
 
 1 
 
 I 
 
 I 
 
 I 
 
 Contagious. 
 Variola 
 
 Non-Contagious. 
 Herpes 
 
 Contagious. 
 Scabies 
 
 Non- Contagious* 
 Lichen 
 
 Vaccinea 
 
 Erythema 
 
 Pityriasislutea 
 
 Lepra, or 
 
 Varicella 
 
 Ecthyma 
 
 Leprosy 
 
 Psoriasis 
 
 Scarlatina 
 
 Furunculus 
 
 
 Pityriasis 
 
 Rubeola 
 
 Anthrax 
 
 
 Ichthyosis 
 
 Roseola 
 
 Purpura 
 
 
 Impetigo 
 
 Erysipelas 
 
 Sudamina 
 
 
 Rupia 
 
 Frambcesia 
 
 Miliaria 
 
 
 Eczema 
 
 
 Urticaria 
 
 
 Molluscum 
 
 
 Pemphigus 
 
 
 Vitiglio 
 
 
 
 
 Cancer 
 
 
 
 
 Lupus 
 
 
 
 
 Elephantiasis 
 
 3. CLIMACTERIC INFLUENCES 
 produce 
 
 Foetal. 
 Naevus 
 
 Infantile. 
 
 Adolescent 
 Acne simplex 
 
 Contagious. Non- Contagious. 
 Ring-worm Stropbulus 
 Scald head Crusta lactea 
 
 I ! . 
 
 Adult. Senile. 
 
 Acne rosacea Prurigc 
 Sycosis senilis 
 
SUPPOSED PARASITIC ORIGIN. 21 
 
 tioned by Willan which are not included in Hunt's table 
 are pompholyx, ephelis, spilus, and aphthae. But as the 
 first is only another name for pemphigus ; ephelis a 
 form of pityriasis ; spilus a kind of nevus; and aphtha 
 a parasitic growth occurring in the mouth during child- 
 hood ; these may be eliminated. 
 
 PARASITIC DISEASES GENERALLY. 
 
 Before I fully enter upon the question of the so-called 
 parasitic diseases of the skin, it is necessary to observe 
 that I am about to reproduce the results of observa- 
 tion commenced in 1856, and extending over several 
 years, to ascertain the nature, origin, and supposed in- 
 fluence exercised by certain minute vegetable organisms, 
 which the microscope has enabled us to detect in con- 
 nection with human skin affections. I may likewise 
 add, at starting, that subsequent investigations tend 
 to confirm the conclusion at that time come to, that 
 fungi were not necessarily the cause, but more probably 
 the effect, of the morbific condition. It is therefore 
 more than ever necessary that attention should be 
 steadily directed to the elucidation of this important 
 question whether the parasite be capable of originating a 
 specific disease ? otherwise we may be liable to mistake 
 the shadow for the substance. At the same time, I do 
 not deny that the spores of a fungus may aggravate a 
 condition of disease ; that is, when an eruptive or abraded 
 surface offers a favourable soil for the growth of a para- 
 site, it takes root and flourishes : this is seen to occur 
 among plants of unhealthy growth. 
 
 It is believed that there is a tendency among plants 
 
 and animals to become affected by a parasitic growth ; 
 
 and this may be increased by atmospherical conditions, 
 
 such as those known to favour the spread of an 
 
 \)idemic disease. I have observed, during the preva- 
 
22 SKIN DISEASES OF A 
 
 lence of a close, moist state of the atmosphere, that 
 fungi abound; while in an opposite condition, fine, dry 
 weather, or brisk, frosty weather, they quite disappear. 
 This is not remarkable, as eggs and seeds lie dormant at 
 such times and seasons, and many forms of vegetation, 
 as the protococcus, grow only when the air is moist, and 
 when dry remain perfectly quiescent. Vibrio tritici, wheat- 
 cockle, can be kept inactive for years, and the powers 
 of the cerebrum of birds suspended by freezing. It is not 
 surprising, therefore, that diseases of the skin, accom- 
 panied by a parasitic growth, are rarely met with during 
 certain states of the atmosphere. It is noticed also that 
 seasons bring round with them especial outbursts of 
 disease ; and perhaps this is why we find the spores of 
 aspergittus, penicittium, and puccinia, more widely distri- 
 buted both in town and country towards the end of the 
 hot weather ; about autumn time they are everywhere 
 more abundant. Among those who have taken them at 
 this period of the year, I may name the Rev. Lord S. 
 Godolphin Osborne, who, during the cholera visitation 
 of 1858, exposed prepared slips of glass over cesspools, 
 gully-holes, &c. near the dwellings of those suffering 
 from the disease, and caught what he named aerozoa 
 minute germs and spores of fungi represented in fig. 1.* 
 I have again and again amu&ed myself by catching these 
 floating atoms, which may be found everywhere, and in 
 and on every conceivable thing. Even the open mouth 
 is an excellent trap for them: of this there is ample 
 evidence, since on the delicate membrane lining the 
 mouth of the sucking, crying infant, and on the diph- 
 theritic sore throat of the adult, the O'idium albicans is 
 
 * Mr. Glaisher, during cholera epidemics, noticed the constant 
 occurrence of a dense blue mist ; slides exposed during the prevalence 
 of this atmospheric phenomenon, and examined under a high power, 
 exhibited numerous organic particles, fungi, &c. 
 
SUPPOSED PARASITIC ORIGIN. 23 
 
 often discovered. The human or animal stomach is also 
 sometimes invaded : in a certain deranged condition, the 
 Sarcina ventriculi, and its remarkable-looking quaternate 
 spores, seriously interfere with the functions of digestion. 
 The same class of vegetable organism occur in con- 
 nection with skin diseases. The whole genera belong to 
 a division of acotyledonous plants, called by botanists 
 Thallophytes and Gellulares ; plants composed of cellular 
 tissue only, having neither stem, leaves, nor stomata, and 
 reproduced by spores ; in fact, the lowest forms of 
 vegetable life, which alike, from their extreme simpli- 
 city of structure, puzzle the botanist and zoologist. The 
 fungi mostly appear as a thallus, supported upon a 
 fine thread, with spores or seeds on the under surface of 
 the hymenium. By far the greater part of them live in 
 the air, a few in water, always mysteriously making their 
 appearance upon the surface of decaying organic matter. 
 They are very fugacious, springing up in a night, arriving 
 at maturity by noontide, and disappearing magically. 
 I must briefly describe one or two of the commonest 
 of the fungi, better known as moulds, or mildews. The 
 simplest in form and structure is the yeast plant (see 
 fig. 2), which, in its most perfect condition, is made up 
 of globular vesicles, measuring, when fully grown, about 
 the -arW^h of an inch in diameter. The older cells 
 are filled with protoplasmic granular, nucleated matter ; 
 the nucleus rapidly increases, and nearly fills the parent 
 cell, which then becomes ovoid ; ultimately young cells 
 bud out and are separated from the parent. Sometimes 
 other and smaller cells are formed within the young 
 one before it leaves the parent globule. This process is 
 incessantly repeated, that is, so long as a supply of food 
 lasts. The vesicles, it appears, derive their nourishment 
 by a process of osmose, sucking in, as it were, certain 
 portions of the organic fluid, and chemically decom- 
 posing it; appropriating a part of its nitrogen, and 
 
24 SKIN DISEASES OF A 
 
 giving off carbonic acid. If, however, it is placed 
 in any adverse condition, it becomes surrounded by a 
 layer of condensed matter, resulting from the death of 
 the germinal material, and ultimately a trace only of life 
 remains, which, dying, takes the form of an impalpable 
 powder, and is driven hither and thither with every 
 breath of air. 
 
 I am justified in saying that there appears to be a 
 difference in the results obtained by brewer's yeast 
 and those obtained by penicillium. I cannot, however, 
 agree with M. Pasteur that the different fermentations, 
 the vinous, the lactous, and the acetous, are produced 
 by different species of fungi ; nor have I discovered that 
 brewer's yeast belongs to another genus, although it may 
 be a different species. The difference observed is that 
 the brewer's yeast cell is quite circular in form, pale in 
 colour, the cell wall is thin, and its contour not so well 
 marked ; it is filled with a granular matter, described as 
 nuclei, varying in number from five to ten, and as soon 
 as the solution becomes exhausted, the cell wall is 
 ruptured, and the granular matter escapes, when, if 
 fermentation is not soon stopped, bacterium-like bodies, 
 vibrios, are produced, and acetous fermentation begins. 
 In the other kind of cell, by far the more important of 
 the two, the cell wall is thick, and its contour well marked, 
 the interior is filled with a highly refractive protoplasmic 
 mass, the central nucleus is faintly seen, at times is not 
 made out until the solution is nearly exhausted, when 
 the cell has a tendency to become ovoid in form, and 
 sometimes considerably elongated. The cell in its early 
 life is precisely like the German yeast cell, and which is 
 mysteriously developed. It is doubtless identical with 
 the fungus found floating in the air ; and when it ger- 
 minates in vinous solutions, it grows to a much larger 
 size ; under certain conditions it bears a resemblance to 
 the fat corpuscle, and probably has been mistaken for 
 
SUPPOSED PARASITIC ORIGIN. 25 
 
 it. I term this the albuminoid form of cell, because the 
 presence of albumen seems to add to the vigour of its 
 growth. But the most remarkable fact in connection 
 with this fungus is that it produces ten per cent, more 
 alcohol than its congener, and does not become so readily 
 exhausted as brewer's yeast. It is impossible for me to 
 offer any explanation of this fact ; the spores must float 
 about in an almost impalpable dust, and it does appear 
 that a dry powder, equally with an extract of yeast, is 
 all that is necessary to bring about a transformation of 
 sugar into alcohol.* 
 
 It is curious also to notice that, with the exhaustion 
 of the glucose, levulose, or dextrose, the development of 
 vibrios or bacterium-like bodies occurs, at the same time 
 the lactic acid change begins, and a destructive process 
 ensues. The cell walls appear to supply food for these 
 low forms of organisms, which ultimately die off, and 
 are succeeded by other generations. A large quantity 
 of albumen seems to be produced by the contact action 
 of these aerozoa; but if this substance is greatly in 
 excess, the solution is more prone to a destructive 
 ferment, especially so if cellulose be present at the same 
 time. A remarkable instance of this has been brought 
 to light. The Batrachospermese are algae, living in a 
 sort of albuminous envelope, and their zoospores are 
 
 * Liebig's latest investigations were nearly conclusive that the 
 yeast fungus (Cerevisia torulce)^ if it plays any part, it is a very unim- 
 portant one, in the process of fermentation, or the transformation of 
 glucose into alcohol and carbonic acid. This great chemist considered 
 fermentation to be a purely chemical or physio-chemical process 
 brought about by heat. " It is possible," says Liebig, " that the phy- 
 siological process stands in no other relation to the process of fermen- 
 tation than that, by means of it, a substance is formed in the living 
 cell, which, by an action peculiar to itself (resembling that of enmlsin), 
 determines the decomposition of sugar and other organic atoms. In 
 such case, the physiological action would be necessary for the produc- 
 tion of this substance, but would be otherwise unconnected with the 
 fermentation properly so called." 
 
 C 
 
26 SKIN DISEASES OF A 
 
 aggregated in cells. On placing masses of this algae in a 
 bottle, and adding fresh water, a spontaneous ferment is 
 soon set up, the seed-vessels burst with the disengage- 
 ment of gas; after this operation the colour of the 
 liquid changes ; it assumes a delicate pink in direct light, 
 which deepens to a reddish hue in condensed light ; the 
 fluid is now dichroic, it is fluorescent, and the spectro- 
 scopic appearance is one of interest : the spectrum is a 
 well-marked one, and may ultimately assist in determin- 
 ing the presence of albumen in animal and vegetable 
 solutions. It certainly appears that the physiological 
 action set up in fluids, having an excess of albumen 
 present, is one which differs considerably from the 
 chemical changes observed under other conditions. 
 
 Dr.Thudichum revived a curious experiment the im- 
 mediate conversion of cane sugar into grape sugar. If 
 we take two parts of white sugar, and rub it up in a 
 mortar, with one part of a perfectly dry solid the 
 so-called German yeast it is transformed, as if by 
 magic, into a flowing liquid mass a syrup. This process 
 of forming " invert sugar " can be watched under the 
 microscope ; the liberation of carbonic acid gas in large 
 bubbles is seen to go on, simultaneously with the assi- 
 milation of the dextrose, and breaking up of the crystals 
 of sugar ; the cell increases in size, as well as in refrac- 
 tive power ; a remarkable state of activity appears in 
 the minute mass, which is very interesting. German 
 yeast is a spontaneously fermented mixture of wheaten 
 flour, or malt and water, or honey and malt. I believe, 
 with Dr. Thudichum, that this experiment goes a long 
 way towards " changing our view of the action of yeast 
 in producing fermentation." The transformation is so 
 instantaneous, " that it partakes of the nature of those 
 actions which in chemistry are called * contact actions.' " 
 The amount of moisture retained in the German yeast 
 is very nearly inappreciable ; yet it must be supposed 
 
SUPPOSED PARASITIC ORIGIN. 27 
 
 that there is a minute quantity retained, or the change 
 would not be so very instantaneous* Is, then, the 
 change fermentation, as we call it brought about by 
 simple " contact action," or is it due to organic life ? 
 
 It will be seen on reference to the figures given in any 
 frontispiece, and as I shall presently proceed to show 
 in an experimental and I trust a satisfactory way, that 
 the same species of fungus frequently exhibits varieties 
 of character, as well as form, at different stages of 
 development and under varied influences ; so much so, 
 ** that neither size nor outline affords any basis for dis- 
 tinction into species until it has been ascertained, from 
 extensive comparison of forms brought from different 
 localities in the widest area over which the species can 
 be traced, what are the average characters of the type, 
 and what their range of variation." Dr. Bary, and also 
 Tulasne, established the fact of a wide-spread poly- 
 morphism among fungi. One fungus is actually known 
 to possess six different kinds of fructification, the uredo 
 itself exhibits four, and formerly these were described 
 as distinct species. 
 
 Extreme simplicity of structure characterises all fungi 
 or mildews. Their reproductive organs are somewhat 
 more complex, but less understood; and although at 
 first sight there is a difference in the appearances 
 presented by their fruits, yet this is not sufficient to 
 form a basis for classification. Both in pemcillium, 
 (fig. 5), and aspergillus, the mycelium terminates in a 
 club-shaped head, bearing upon it smaller filaments 
 with bead-like bodies attached to the apex, piled one 
 upon the other, or, more properly speaking, strung toge- 
 ther; these small bodies are termed conidia; others 
 again are surmounted by larger spores of a discoid 
 shape, some filled with granular matter, and others 
 quite empty (fig. 5a). Those of aspergillus are mostly 
 without granular matter or nucleated bodies, and are 
 
 c2 
 
28 SKIN DISEASES OF A 
 
 more highly refractive. The club-shaped Puccinia is 
 the well-known smut or rust, the very rapid growth of 
 the spores and spawn of which appear to exert an ex- 
 haustive action over the tissues of the diseased cereal 
 on which it feeds. 
 
 On repeating experiments made during my investi- 
 gations "On the Vegetable Parasites of the Human Skin," 
 I find little difference, either in the action or results pro- 
 duced in sugar solutions, between yeast fungus, favus 
 fungus, aspergillium spores, and those spontaneously 
 produced in the sweet-wort ; they are equally capable 
 of converting or changing levulose and dextrose into 
 alcohol ; the chemical change is very nearly identical 
 in either case, and the slight differences observed depend 
 more upon the pabulum on which the spores are fed, 
 than upon any other circumstances. Most clearly, 
 diversity in form depends upon food, temperature, &c. ; 
 and whether the fungus is grown upon a sickly plant, 
 an animal tissue, or a saccharine and albuminoid solu- 
 tion. 
 
 Nevertheless, it is attempted to build up a theory of 
 diseases of the skin under a class termed Dermatophyta, 
 as a something sui generis, and quite regardless of the fact 
 that these lowly-organized plants are thereby invested 
 with characteristics utterly at variance with the well- 
 known peculiarities of the family of fungi. 
 
 My inquiry then resolves itself into a definite one, 
 namely : Is the diseased condition of the cutaneous 
 surface due to the ravages of a vegetable parasite? 
 or is the appearance of the vegetation the result 
 of disease ? This is a question upon which I propose to 
 enter, and undoubtedly it is one of some practical im- 
 portance ; for if the disease is produced by the parasite, 
 we have only to destroy the latter and a cure is certain 
 to follow. If, on the other hand, the parasite only acts 
 the part of a scavenger, the province of which is to 
 
SUPPOSED PARASITIC ORIGIN. 29 
 
 remove materies morbi, then we must seek to rectify 
 the condition on which the disease depends, and the 
 parasite will be starved and disappear for lack of food. 
 Every one knows that decaying substances are the seat 
 of fungoid life ; that the mould that infests the stores 
 of the thrifty housekeeper, and the fungi growing in 
 damp and rotting wood, are illustrations of this fact. 
 These low forms of vegetable life exist on decaying 
 matter ; the decomposing process is their food, and 
 becomes an organizing process in them; the force 
 arising from the decomposition becomes and is their 
 vital force. The life of the wood has in short been 
 transformed into the fungus. The force has changed 
 its form ; but it is the same force in both. The fungus 
 could not have grown if the wood had not decayed. 
 
 It scarcely admits of a doubt that all the diseases 
 observed of late in our vines, fruits, and growing crops, 
 are the result of some atmospheric condition, as well as 
 an exhaustion of the plant or seed a want of vigour 
 arising out of loss of chemical elements in the soil 
 and the air it breathes, which predisposes the plant to 
 become an easy prey to " the murrain " or the fungus.* 
 The microscopic germs of these lowly-organized vegeta- 
 tions are produced in millions ; invisible though they be 
 to the unaided vision, they make their presence known 
 only when seen in myriads upon the earth, in the air, 
 and water. Wonderfully minute are their spores, and 
 equally wonderful their rapidity of germination and 
 growth. The old sawn stump of a tree, after a warm 
 and rainy night in autumn, is found covered with large 
 agarics on the following morning. A spotless meadow 
 
 * " The potato, the vine, the hop, the elm, suffer ; and aphides, sco- 
 lyti, fungi, and other parasites abound. Without denying to these 
 some effect, the facts show that the prime cause is the weakness of the 
 nutritive forces of the individual, and that the parasitic animals and 
 vegetables are the accident." Dr. Morris. 
 
30 SKIN DISEASES OF A 
 
 has been known to be covered within forty-eight hours 
 with puff-balls, many of which are as large as the 
 human head; and a snow-covered country changed 
 in a night to a deep red colour, by the protococcus 
 nivalis, gory-dew, or red snow of the northern regions. 
 
 It will not be denied that the universality of distri- 
 bution of .the fungi is in itself a fact of considerable 
 importance, and one pointing to the belief that they are 
 ordained to become scavengers, ready to fasten on the 
 disintegrating particles of organized matter destroyed 
 by disease and undergoing the chemistry of re-construc- 
 tion by death. A very special purpose have these minute 
 bodies to fulfil in the economy of nature : when any 
 animal or vegetable body sinks below the standard 
 necessary to maintain it in tolerable vigour, fungi x 
 themselves upon it, and, finding a suitable soil, grow 
 and spread out their pellucid filaments in every direc- 
 tion and in dense masses, and in so persistent a 
 manner as to arrest any further act of development. 
 
 In a similar way the epidermic structures of the 
 human body may be entirely excluded by a fungoid 
 growth from the salutary influences exerted by air and 
 light, and prevented from giving out, exhaling, the accu- 
 mulated carbonic acid, and in this way aggravate and 
 hasten on a destructive form of disease. Such a mode of 
 progression in the low forms of vegetation is actually 
 seen to occur when the vine is attacked by the oidium, 
 a fungus described by botanists as a perfect plant, but 
 which really is an imperfect condition of one of a 
 more complex nature. The spores fasten themselves to 
 the outer coat of the young grape, and, although 
 internal development may proceed for a time, the spha- 
 celated epidermis can no longer expand, and either bursts 
 in growth, or further development is so entirely arrested 
 that it withers and dies. This kind of arrest and death 
 is known to take place when a silkworm is fed on un- 
 
SUPPOSED PARASITIC ORIGIN. 31 
 
 wholesome food, or is improperly exposed to wet or 
 damp without sunlight ; it then falls a victim to the 
 dreaded muscardine. Animals having the highest and 
 most perfect organization speedily succumb to similar 
 deteriorating influences; there is no immunity when 
 nature's laws are infringed or disregarded. 
 
 Seeing, then, that the fungi are characterised through- 
 out nature by feeding on effete or decayed matter ; that 
 fungi supposed to. be peculiar to certain diseases of 
 the skin are also found in many other diseases of the cu- 
 taneous surface ; that competent observers have not been 
 able to find them in these peculiar diseases ; that spo- 
 rules and filaments, described as the cause of one definite 
 disease, have been found in the products of another 
 form of disease supposed to have a peculiar and distinct 
 parasite of its own ; and that attempts to implant these 
 parasites in a healthy skin have almost invariably failed ; 
 one cannot but conclude that special parasites, peculiar 
 to and productive of special diseases, do not exist. This 
 opinion gathers strength from the therapeutical fact that 
 the alleged parasitical affections are rarely, if ever, 
 cured by destroying the parasite ; while they can be 
 cured by the due administration of appropriate alterna- 
 tives and tonics, which are capable of correcting the 
 blood dyscrasia, which, in truth, originates the disease.* 
 
 Various Opinions on Parasitic Diseases of the Skin. 
 
 Very considerable differences of opinion exist among 
 authorities on skin diseases as to the part played in 
 certain cutaneous affections by vegetable organism. 
 Professor Bennett of Edinburgh agrees in the main with 
 
 * " British Medical Journal," No. cxvii, March 26, 1859 : The 
 Vegetable Parasites of the Human Skin." By the Author. 
 
32 SKIN DISEASES OF A 
 
 the views I have expressed. He maintains that the pa- 
 rasitic growth is a secondary matter found in a living 
 animal previously the subject of deranged health. Dr. 
 Tilbury Fox expresses similar views, and says that the 
 fungus should be regarded as a something superadded 
 to the diseased condition. " A complex condition, an 
 eruptive disease plus a tinea" (parasite). In other 
 words, " the pathognomonic sign of a parasite disease of 
 the surface is the infiltration and destruction of the 
 hairs by the spores ; and the diagnosis can in no wise be 
 considered perfect until spores or mycelia have been 
 detected by the microscope." I do not quite agree with 
 this definition of the diseased condition, nor can I admit 
 that the growth of a fungus is necessarily pathognomonic 
 of any special form of disease. Other observers of 
 eminence go much further than this, and hold that the 
 fungus is solely the cause of the disease ; and, proceeding 
 on this theory, as I have already observed, give a 
 generic name to each fungus a name derived from 
 the character of the disease and signalizing the species. 
 Sir William Jenner at one time adopted similar views, 
 and taught that the simple way to cure these peculiar 
 affections was to destroy the fungus by some topical 
 application; but the error soon betrayed itself to his 
 mind, and he candidly acknowledged that this mode of 
 treating skin diseases ended in disappointment and 
 failure. 
 
 Kiichenmeister concludes : " that these microscopic 
 discoveries explain not only the pertinacity of the disease 
 since it is well known that the lowest plants develope 
 themselves most intensely and rapidly in a favourable 
 medium but also its contagious character, which is no 
 longer doubtful. The fungus itself is the sole cause of 
 these changes of the hair, and of the secondary irritation 
 and congestion of the skin, which cause exudation, an 
 accelerated formation of the epidermis, scaling off and 
 
SUPPOSED PARASITIC ORIGIN. 33 
 
 production of crust, because the swollen hair exerts 
 pressure on the skin."* 
 
 I may here once more remark that it is scarcely 
 possible to show that these microscopic germs are in any 
 way the cause of any special form of disease, although 
 I can go further than Kiichenmeister and most observers, 
 in having discovered fungoid bodies in connection with a 
 larger number of chronic skin diseases, and in some of 
 which it was not before supposed they had an existence. 
 Thus, out of twenty cases and upwards of lepra and 
 psoriasis, evidences of a fungoid growth were seen in 
 half of them. The same was noticed in two out of three 
 cases of lichen ; in four out of six of eczema, etc. Other 
 competent observers, however, have not been able to 
 discover them in the diseases thought to be engendered 
 by vegetations. Malherba, Wilson, and Cazenave, doubt 
 the existence of a vegetable fungus in porrigo scutulata 
 (the common ringworm) ; or if, as Professor Wilson 
 observes, the cryptogam should be formed, " I by 
 no means admit that it is the origin of the 
 disease: it is rather a secondary or adventitious pro- 
 duct." The same remarks apply to the presence of 
 achorion Schdnleinii in connection with favus, and also 
 microsporon andonini in porrigo decalvans. It is not 
 denied that fungoid growths do occur in connection with 
 certain forms of skin disease; but that they are sur- 
 rounded by special characters, and afford a basis for 
 classification, is utterly untenable. Thus, in a case of 
 porrigo which occurred in a girl 16 years of age, ill- 
 nourished, neglected, and dirty, I found no porriginous 
 variety of fungus but one, described by Robin and 
 Kiichenmeister as peculiar to plica Polonica, a disease 
 almost unknown in this country. Again, in a case of 
 
 * Kiichenmeister's " Manual of Parasites," p. 144. Sydenham 
 Society's translation. 
 
34 SKIN DISEASES OP A 
 
 tinea tarsi, I found spores of the fungus described 
 by Ardsten as puccinia favi spores represented in fig. 1. 
 Robin also discovered, in some cases of favus, puccinia, to- 
 gether with achorion schonleinii. The latter were mixed 
 up as a constituent of the crusts, while the former ap- 
 peared to be superadded during the desquamation of the 
 epidermic scales. Some observers have, in consequence 
 of this, taken the achorion to be the spermagonial form 
 of the puccinia. It has been also broadly asserted 
 that the several morbid conditions observed in chronic 
 diseases of the skin are mutually convertible, the one 
 into the other; and therefore that lichen, eczema, 
 impetigo, psoriasis, and lepra, are only modifications of 
 one and the same form of disease ; that variety is but 
 an accidental modification, produced by constitutional 
 causes ; and dermatologists themselves seem to favour 
 this idea, by assigning names to certain diseases which 
 are indicative of a mixed character as eczema impeti- 
 ginodes, eczema leproides, lichen urticatus, erythema papu- 
 latum, and so on.* 
 
 It will be said, no doubt, that many of the cases 
 
 * Dr. H. S. Purdon has seen herpes circinatus and favus occur at 
 the same time. Upon examining the back of a fever patient 18 years 
 old, he found several patches of herpes circinatus, and which she stated 
 had existed for nearly three years. In the middle of the patches a 
 circular spot of favus was noticed, about the size of a penny ; this 
 was recent. During the progress of the case it was interesting to 
 observe the action of the fever, so to speak, upon the eruption ; the 
 patches of herpes all but disappeared, and the favus became dry and of 
 a whitish colour, losing its sulphur-coloured appearance. As soon as 
 convalescence was established, little vesicles showed themselves around 
 the margins of the eruption, and which rapidly assumed a spreading 
 character. This is the third case in which Dr. Purdon has observed 
 the occurrence of favus and herpes circinatus in the same subject, 
 showing the identity of the fungus, which, in a more matured form, 
 allows of the development of fungus. The secretions, he tells us, are 
 usually acid in patients in which vegetable parasites appear; and hence 
 their greater frequency in the strumous diathesis. 
 
SUPPOSED PARASITIC ORIGIN. 35 
 
 examined by me belonged to this category, and there- 
 fore the finding of parasitic fungi in connection with 
 them, might, a priori, have been expected. My first 
 batch of cases were selected under the practised eye of 
 my friend Mr. Hunt, and were taken as typical of the 
 forms of disease under which they are enumerated and 
 described. 
 
 A word or two on the mode of examination adopted. 
 Each specimen, soon after removal from the body, was 
 submitted to a microscopical examination ; and, in order 
 to avoid errors of interpretation, it was likewise subjected 
 to the action of various reagents the drawings being 
 made under a power varying from two to four hundred 
 diameters, by an independent observer, one accustomed 
 to work of the kind. In my description of the several 
 skin affections examined, it is not my intention to adhere 
 to any particular order or classification of diseases. 
 I shall rather take them in their order of importance in 
 connection with the parasitic said to originate them ; and 
 on the continent, where this theory first found favour, 
 favus occupies the post of honour. 
 
 PORRIGO FAVOSA. 
 
 Porrigo favosa. Syn. Favus ; porrigo lupinosa ; favus 
 disperses; honey-comb scall. (Achorion Schonleinii, 
 figs. 6 and 7.) 
 
 Under the name of porrigo lupinosa Willan and 
 Bateman describe a peculiar form of disease rarely seen 
 in this country, while on the continent, where it is more 
 common, the affection has received the name of favus. 
 During a long period of attendance at the Dispensary for 
 Skin Diseases, I saw only three cases of this affection, and 
 from all I was fortunate enough to obtain a good supply 
 
36 SKIN DISEASES OF A 
 
 of scales. It is admitted that favus is essentially a 
 disease arising out of misery ; indeed it is rarely seen 
 except in persons broken down in health, badly fed, or 
 suffering privation, and living in dirt and poverty. 
 Various theories have been broached of the pathology 
 of favus, some believing it to be primarily a pustular 
 affection, while others say it is a morbid secretion of the 
 sebaceous glands, a tubercular modification of tubercle 
 in the lungs, and so on, while more recently its vegetable 
 nature and origin is insisted upon. Professor Bennett 
 writes, "I believe that the pathology of favus is best 
 understood by considering it essentially to be a form of 
 abnormal nutrition, with exudation of a matter analagous 
 to, if not identical with, that of tubercle, which consti- 
 tutes a soil for the germination of cryptogamic plants, 
 the presence of which is pathognomonic of the disease. 
 Hence is explained the frequency of its occurrence in 
 scrofulous persons, among cachectic or ill-fed children, 
 and the impossibility of incubating the disease in 
 healthy tissues, or the necessity for their being scaly, 
 pustular, and vesicular eruptions on the integuments 
 previous to contagion. But assuming the possibility of 
 inoculation in healthy persons, it follows that the 
 material in which the vegetations grow may, at the com- 
 mencement, in a molecular exudation, be formed pri- 
 marily or secondarily. That is, there may be want of 
 vital power from the first, as occurs in scrofulous cases ; 
 or there may have been production of cell forms, such 
 as those of pus or epidermis, which, when disintegrated 
 and reduced to a like molecular and granular material, 
 secondarily constitute the necessary ground from which 
 the parasite derives its nourishment, and in which it 
 grows."* Professor Erasmus Wilson, who has often 
 
 Principles and Practice of Medicine, page 807. 
 
SUPPOSED PARASITIC ORIGIN. 37 
 
 examined favus crusts, is opposed to the notion that 
 the disease owes its essential characters to a vegetable 
 growth ; he considers that the tubular and ovoid bodies 
 are mere modifications of epidermic cells, which in some 
 cases are actually converted into pus-globules. His 
 words are, " the favus matter is produced from the 
 development of the nuclei of pus-cells ; the parasite is 
 not a vegetable ; or, if it be, it might be looked upon as 
 an example of the conversion of an animal into a vege- 
 table product/' In his opinion these bodies are a mere 
 resemblance to a vegetable formation, and consequently 
 the statement of the origin of the vegetable formation 
 by roots implanted in the cortex of the crust is un- 
 founded, and the secondary cells (sporules) bear no 
 analogy to sporules or seeds ; and it is therefore unrea- 
 sonable to assign to an organism so simple as a cell the 
 production of seeds, and reproduction thereby, when 
 each- cell is endowed with a separate life, and separate 
 power of reproduction. 
 
 The vegetable nature of the growths, and their analogy 
 to other well-known fungi, as the penicillium glaueum, or 
 aspergilius penicillatus^ is beyond dispute ; but as to the 
 possibility of growing the fungus spores on the healthy 
 human skin I have considerable doubts. I have fol- 
 lowed Remark's experiments, and made attempts to 
 inoculate the skin of healthy persons without success. 
 In certain unhealthy conditions, and where there is an 
 already abraded skin to experiment upon, fungoid spores 
 may be made to germinate. In the one or two almost 
 isolated instances of a success in this direction, it appears 
 that crusts were bound on to an irritated part of the 
 skin, or where pustules of some kind already existed, 
 and after a period of incubation the disease has been 
 established. It is stated that an acid state of the 
 secretions, or some chemical change going on in the 
 skin, is an essential element in such experiments. 
 
38 SKIN DISEASES OF A 
 
 Favus consists of an exudation from the cutaneous 
 surface in which fungoid elements are found. The dis- 
 ease has been variously described, and under the several 
 names of porrigo favosa (favus, a honey-comb), porrigo 
 lupinosa (lupinum, the lupine), trichosis lupin osa, 
 and tinea favosa. The affection first shows itself as 
 round isolated spots of a bright yellow colour, which pre- 
 sent a certain resemblance to the lupine seeds ; these 
 run together and form crusts of an hexagonal, honey- 
 comb shape. The formation of pustules is not an 
 essential of the disease, and therefore it is a mistake to 
 classify favus among pustulse (Bennett). These, how- 
 ever, do occasionally appear as a secondary result, and 
 when desquamation of the cuticle is rapidly taking place. 
 In the few cases I have seen, the disease had fairly estab- 
 lished itself, and the skin was quite of a pale colour, and 
 without any increased vascularity; while the desqua- 
 mation of scales was extremely large, amounting in 
 weight from four to six ounces daily. In one case the 
 scales were more disseminated, and formed a thick mass ; 
 the crusts were almost entirely composed of fungoid 
 filaments, epithelial scales, and broken hairs. The 
 fungus having fairly established itself on one part, it 
 rapidly spread over the whole of the surface of the 
 body, the palms of the hands and soles of the feet 
 forming the only exceptions. The hairs were shriveled, 
 and without colouring matter, and most of the surface 
 entirely bald. 
 
 The constitutional symptoms are marked in most 
 cases ; and a deranged state of health is associated with 
 enlarged lymphatic glands of the neck, or of the 
 mesentery, and lung mischief. If the disease does not 
 soon yield to tonics or good food, the skin assumes a 
 mealy look, the crusts spread with increased irritation, 
 and emit a disagreeable odour not unlike the smell of 
 mice, and from this circumstance it derives the name of 
 favus. 
 
SUPPOSED PARASITIC ORIGIN. 39 
 
 The surface becoming almost denuded of hair is 
 explained in this way : The shaft of the hair consists 
 of hardened, shrunken, epithelial cells, almost devoid of 
 germinal matter; and being removed some distance 
 from the bulb with a weakened vital power, is less able 
 to resist the parasite, which gradually cuts off nutri- 
 tion, and ultimately destroys vitality. In this case, the 
 fungus feeds upon the dying and the dead, and not 
 upon healthy material. 
 
 If we take a crust and carefully examine it, we shall 
 find that it is comprised of an outer and older part, 
 thick and dark in colour ; the fungus is here in a more 
 advanced stage of growth, and consists of sporangia, 
 spores, and mycelia, with fragments of hairs and pus- 
 like bodies, while the inner or younger layer is paler in 
 colour, and consists of spores with epithelium, fatty, 
 granular, and purulent matter. 
 
 M. Gruby, who first described the microscopical ap- 
 pearances of the favus crust, gives the following direction 
 for preparing specimens for examination under the mi- 
 croscope. Cut a thin section of the crust or capsule 
 quite through, making it embrace the outer layer of the 
 epidermis, amorphous mass, and light friable matter in 
 the centre. This, under a power of 300 diameters, will 
 be seen to consist of cylindrical tubes (thatti) springing 
 from the sides of the capsule, and giving off branches 
 dichotomously ; when fully developed, they terminate 
 in mycelia and a large number of round or oval spores 
 (sporidia] . The sides of the threads or tubes varies from 
 the 1-400 to 500 of a millimetre in thickness, and they 
 are jointed at irregular intervals. The mycelia and 
 sporules agglomerated in masses are always more abun- 
 dant and fully developed in the centre of the crust, 
 while the thalli are more numerous near the external 
 layer. The hairs which pass through the centre of 
 the favus crusts are occasionally healthy, but more fre- 
 
40 SKIN DISEASES OF A 
 
 quently they are brittle and covered with threads and 
 spores, which produce atrophy of their bulbs and subse- 
 quent baldness. 
 
 The physical aspect of persons suffering from favus 
 is very remarkable ; because, as I have already stated, 
 this disease is the embodiment, or rather the imper- 
 sonification, of a weakly, unhealthy state of the body, 
 called by some a scrofulous habit ; and associated with 
 dirt and neglect. Hebra, the great authority on skin 
 diseases, lays much stress upon the feature of dirtiness 
 as a cause of favus, and observes that this accounts for 
 its rarity among the upper classes of society. The sub- 
 ject of one of the worst cases I have yet seen was a 
 puny, half-starved boy of seventeen, whose appearance 
 was that of a child of nine or ten. When taken from 
 his miserable home into purer air, and well fed, the 
 crusts soon began to die and drop off; but when he 
 returned to his wretched home, situated in one of the 
 filthiest parts of Lambeth, and was insufficiently fed, the 
 vegetation grew again most rapidly " flourishing in the 
 vitiated fluids like a vine in a mass of stercoraceous 
 mould." From this boy I obtained, in 1859, large sup- 
 plies of the fungous crusts, and with which I proceeded 
 to make experiments which quite satisfied me that the 
 favus spores, when added to barley-wort, produce as good 
 a ferment as healthy yeast, with only a slight difference 
 of size, " a difference of degree, and not of kind." Other 
 experiments were subsequently made for the purpose of 
 observing the influence exercised by light upon fermen- 
 tation; and also in what way this agent affected the 
 character of the results. I was, in a measure, led to 
 make these observations from knowing that yeast requires 
 for its more perfect growth, not only a proper tempera- 
 ture, but almost occlusion from daylight a fact that 
 appears to hold good with regard to the development 
 and growth of most fungi. Having procured a supply 
 
SUPPOSED PARASITIC ORIGIN. 41 
 
 of fresh wort from a brewery, I divided it into three 
 equal portions, and, for the sake of convenience, num- 
 bered them 1, 2, and 3. Into Nos. 1 and 2 I put a few 
 favus crusts ; No. 1 was put carefully away in a dark- 
 ened place, the temperature of which was 70 Fahr. ; 
 Nos. 2 and 3 (the latter being simply sweetwort only) I 
 exposed to a good light in my sitting-room window, the 
 temperature of which ranges from 65 to 70 Fahr. ; 
 each bottle was closely corked. On the second day, 
 upon examining a portion of 1 and 2 with a J-inch 
 power, I found fermentation had commenced, a film 
 having spread over the whole surface of the liquid. In 
 No. 1 were seen a fair quantity of yeast-cells, varying 
 in form and size. No. 2 was in a more advanced stage, 
 and some of the spores were rather larger than in No. 1. 
 On the 4th and 5th days I took portions from all three 
 bottles. That from No. 1 gave the best results ; the 
 yeast-cells were more numerous and spherical in form, 
 well filled with granular matter and numerous monili- 
 form chains of smaller spores and amorphous stroma. 
 Compared, however, with a small portion of fresh yeast 
 from a beer barrel, the cells and spores appeared to be 
 about half the size. In specimen No. 2 the spherical 
 cells were fewer and smaller, with groups of ovoid spores 
 mixed with torulse, and bacterium-like bodies floating 
 rapidly about ; here and there were seen tufts of peni- 
 cillium. In specimen No. 3 were numerous ovoid spores 
 without granular matter, highly refractive, and not unlike 
 fat globules. 
 
 On the tenth day the changes seen in specimens 
 taken from each bottle were more marked. In No. 1 
 the spores were more numerous, but certainly smaller, 
 and variable in form, and the greater portion of them 
 were filled with granular or nucleated matter ; there were 
 also groups of torulse mixed with smaller spores (see 
 fig. 6). This specimen, when the cork was removed from 
 
42 SKIN DISEASES OF A 
 
 the bottle, gave indications of the presence of carbonic 
 acid, the odour was that of good fresh beer, and the 
 greater portion of the heavy yeast had fallen to the 
 bottom of the bottle. No. 2, on the contrary, had be- 
 come of a dark colour, smelt sour, and the spores had 
 diminished in size, granular matter and bacteria being 
 more numerous. The wort in No. 3 was still sweet of 
 a somewhat vinous sweetness and the top was thickly 
 covered over by a whitish, flocculent, filamentous-looking 
 mass of penicillium. 
 
 A fortnight or rather more elapsed, and another 
 examination gave somewhat similar results. No. 1 was 
 still perfectly sweet, while No. 2 was more sour, and of 
 a dark red colour ; the filamentous masses were broken 
 up, and had fallen to the bottom of the fluid, and the 
 surface was slightly covered with a mould. No. 3, 
 although smelling somewhat like bad wine, was not much 
 altered in colour, and on its surface aspergillus was 
 growing (fig. 7). Six months later, No, 1 was perfectly 
 sweet, exhibiting well-marked spores and torulse ; No. 2 
 was rather more decomposed than it was on the former 
 examination ; No. 3 remained in the same state. 
 
 Upon comparing the fermentation of the achorion 
 fungus with that of good healthy yeast, it was almost 
 identical, and the influence exercised by light and tem- 
 perature was marked ; the difference in the size of the 
 spores or cells was slight, the yeast cells being some- 
 what larger and more nearly spherical, with a greater 
 number of reproductive spores, but having only a slight 
 tendency to coalesce or become filamentous, while the 
 favus ferment produced a greater number of ovoid cells, 
 with a proneness to coalesce and bud out into torula3. 
 With reference to the slight difference in size, we may 
 look upon this as a matter of little importance ; for to 
 the presence of light in the one case, and its almost total 
 exclusion in the other, this difference, I have no doubt, 
 
SUPPOSED PARASITIC ORIGIN. 43 
 
 was almost entirely due. It would be more trustworthy 
 if comparisons of this kind could be made at the same 
 stage of development ; for be it remembered that yeast 
 obtained from a brewery is in a more favourable state for 
 experiment, inasmuch as it is stopped at a certain stage 
 of growth or development, and then set to begin its fer- 
 mentation over again in fresh supplies of a new wort or 
 pabulum, which gives increased health and vigour to the 
 plant ; whereas the favus fungus is obtained and used 
 in an exhausted state, and taken from an ill-nourished 
 or starved soil. Neither must we attach much import- 
 ance to differences in size and form of the spores, as 
 this also occurs in yeast ferment; the ovoid form, 
 although most frequently seen in achorion, is equally 
 common to yeast when exhausted. To ensure success 
 in these and similar experiments, the fungus or yeast 
 should be left floating on the surface of liquids ; fermen- 
 tation is either carried on very slowly or is entirely 
 arrested by submersion. 
 
 Turpin and others, experimenting with yeast, noticed 
 in every case that the cells become oval and bud out in 
 about an hour after being added to the wort ; this how- 
 ever quite depends upon temperature and density of 
 solution, as well as upon the quality of the yeast. It is 
 a fact that when yeast is added to distillery wash, which 
 is always worked at a higher temperature than brewers' 
 wort, fermentation commences earlier, and the yeast- 
 cells grow to a much larger size. It is in this way forced 
 much as a plant in a hothouse is, and obtains to greater 
 perfection in a shorter time ; but if again used as a 
 ferment it is sooner exhausted, and therefore, if a small 
 portion of this yeast be added to barley-wort and kept at 
 a temperature of from 60 to 65 Fahr., it ferments lan- 
 guidly, and small yeast-cells are the result. If the yeast 
 is allowed to stand in a warm place for a few days, it 
 partially recovers its activity, never wholly. With such 
 
44 SKIN DISEASES OF A 
 
 a yeast there is always a good deal of torulse mixed 
 with the germinating cells, and sometimes a filamentous 
 mass that falls to the bottom of the vessel; in this 
 condition it readily passes to must and mildew, and 
 then becomes a wasteful feeder or destroyer. 
 
 In other experiments, I took portions of penidllium 
 and aspergillus moulds ; upon adding these to sweet wort, 
 I obtained results confirmatory of Dr. Lowe's,* and 
 which were as follows: Having placed the spores in 
 the wort, I stood them by in a warm room for observa- 
 tion. On the second day in one of the solutions, and 
 on the third in the other, fermentation had fairly set in ; 
 the surface of the solution was covered over with a film, 
 which proved to be ovoid spores, filled with small 
 granular matter (conidid). On the sixth day the cells 
 changed somewhat in form, were more spherical. Again 
 removing these to another supply of fresh wort, the 
 results obtained were quite characteristic of an exhausted 
 yeast ferment. 
 
 In following out the experimental method of research 
 in the way I have endeavoured to point out, I am led to 
 believe that the chemical action set up by the favus 
 fungus in sweetwort is almost, if not quite, identical 
 with that of the well-known ferment, brewers' yeast ; in 
 fact, a line can scarcely be drawn between them, the 
 action of one is s nearly allied to that of the other, in 
 breaking up complex bodies and transforming them into 
 simpler ones. This is not all ; for it appears that other 
 simple plants, as penicillium glaucus, are just as capa- 
 ble of bringing about similar chemical changes by an 
 action or process of fermentation peculiar to themselves, 
 but which is probably controlled by the supply of 
 oxygen. 
 
 * See Dr. Lowe's observations, published in the Edinburgh 
 Botanical Society's Transactions for 1857. 
 
SUPPOSED PAEASITIG ORIGIN. 45 
 
 A word with regard to the apparent differences in 
 the fungi found on the skin. This depends almost wholly 
 on the food or nourishment supplied; whether the 
 pabulum contains more or less of a saccharine, albu- 
 minous, or nitrogenous material, &c. Diversity of form 
 in the cells, as well as quality and quantity of their 
 material contents, is certainly due to, and in a manner 
 regulated and controlled by, the beautiful law of diffusion, 
 which admits, separates, sifts, and refines the coarser 
 from the finer, the lighter from the denser particles 
 of matter, by the agency of the porous cell wall. 
 
 PORRIGO SCUTULATA. Syn. Tinea tonsurans. Trichoses 
 furfuracea. Herpes tonsurant, (Trichophyton ton- 
 surans, fig. 10.) 
 
 Porrigo scutulata (ringworm) in no way partakes of 
 the nature of favus. Although a disease common enough 
 in this country, it is apparently of rare occurrence in 
 France; where for years its history was singularly confused 
 or misunderstood by medical writers. It has been 
 described as tuberculous, vesicular, or pustular, and as a 
 contagious parasitic affection of the scalp. The peculiar 
 tonsure-looking discs ; the furfuraceous secretion ; the 
 dry, uneven state of the skin ; the scattered patches ; 
 the broken, ragged hairs, often surrounded by filaments 
 of a fungus and granular particles, that form a kind of 
 sheathing to the cylinders, and cause them to become 
 less transparent, and break off, when the skin is left 
 bald. The interlacing of the mycelia about the hairs 
 and epithelium partakes of a circular or spiral form, 
 and imparts a ring-like appearance to certain portions 
 of the affected skin. Porrigo scutulata and tinea ton- 
 surans are not unfrequently described as distinct forms 
 of disease ; both are said to be varieties of favus. Be 
 
46 SKIN DISEASES OF A 
 
 this as it may, and after all it is a question of no im- 
 portance, I am convinced that ringworm as well as 
 favus is due to a deranged state of health, and does not 
 originate in the epidermis, nor in the hair, but in the 
 organs of secretion. The vegetation is a secondary pro- 
 duct, and therefore, if attention be paid to the general 
 health, and constitutional treatment resorted to, the 
 most inveterate case of ringworm can be cured. Good 
 air, good food, and tonics always starve the parasite ; and 
 the soil in which it grew and flourished no longer nou- 
 rishes it; the eruption gradually disappears; and the 
 hair resumes its healthy growth. This certainly seems 
 evidence that the disease is not produced by the para- 
 sitic fungus. I have made many examinations of ring- 
 worm, and the following is a summarized statement of 
 its microscopical character : 
 
 Case 1. Ringworm taken at school. In small circular 
 patches about the scalp ; in some parts minute vesicles, 
 the discharge from which converted the scales into thin 
 crusts ; the hair very scanty and friable, mostly broken off 
 short, and standing out abruptly. A fine fungoid 
 growth visible over the surface of the hair, mycelia and 
 filaments branching off in various directions ; epithelial 
 scales shrivelled and abundant. 
 
 Case 2. Ringworm in a sister of the former patient ; 
 the disease presented similar appearances, but the fun- 
 goid growth was not so decidedly developed. 
 
 Case 3. Filaments and fungus spores; the hairs 
 presented peculiar swollen or bulbous protuberances. 
 
 Case 4. Fungus growing as it were out of the hair 
 at its insertion in the skin ; epithelial scales numerous. 
 
 Case 5. A remarkable twisted condition of the hair, 
 which was covered with fungus spores, but no filamentous 
 growth. 
 
 Case 6. Hair a good deal matted together by the 
 discharge, and mycelia threads ; a chain of spores pro- 
 
SUPPOSED PARASITIC ORIGIN. 47 
 
 jecting from the hair, as shown in a case of plica polonica 
 by Kiichenmeister. 
 
 Case 7. Ringworm after the dropsy or scarlatina. 
 The hair and epithelium scales matted together in con- 
 siderable patches, in which were mycelia filaments and 
 spores ; the latter in chains a few lines in length. 
 
 Case 8. General health much deranged. Filaments 
 and spores visible about some of the hairs, but not very 
 numerous. 
 
 Case 9. Hair twisted, and split up into a fine tow- 
 like appearance; epithelium scales freely distributed 
 about the patches ; spores of fungus, with fine molecular 
 matter. As these were mixed with a large quantity of 
 fat globules, the examination was somewhat inconclusive. 
 
 The fungus, microsporon, or trichophyton tonsurans, 
 Greely and Gruby tell us, should be found in all 
 cases, spreading about the roots of the hair, and taking 
 a direction up the shaft ; while the microsporan audouini, 
 the supposed parasite of porrigo decalvans, produces a 
 kind of tubular growth around the external part of each 
 hair, and not in the follicles or beneath the skin. I have 
 been unable to verify this statement, nor do I think it 
 can be maintained ; it is, however, of no diagnostic value 
 in determining the treatment of the disease, the patho- 
 logy of which is a deranged condition of the healthy 
 functions of the skin. Above all things it is necessary 
 to direct particular attention to the general health, and 
 employ a tonic regimen, when the irritation and erup- 
 tion speedily disappear. 
 
 PORRIGO DECALVANS. Syn. Tinea decalvans. Alopecia. 
 (Microsporon audouini, figs. 8 and 9.) 
 
 My next illustration is drawn from Willan's fifth 
 order of skin diseases, Pmtulce, so called because most 
 
48 SKIN DISEASES OF A 
 
 of them make their appearance in an elevation of the 
 cuticle as a pustule, with an inflamed base, unaccompanied 
 by fever, not communicable, and occurring chiefly upon 
 the arms, legs, and head. By the expression " not ac- 
 companied by fever," Willan intended to imply that 
 these diseases were quite distinct from the eruptive 
 fevers, and the pustules of small-pox and other pocks. 
 Nevertheless, a form of porrigo is believed to be con- 
 tagious, and Willan was evidently of that opinion. 
 
 Ringworm, it is known, rapidly spreads among a family 
 of young children, or in a school, while porrigo decalvans 
 is considered to be of a non-contagious nature, although 
 persons living under the same roof, and the same un- 
 favourable conditions to health, are often seen to be 
 affected at the same time. This disease can scarcely be 
 mistaken for the baldness of age, or premature decay of 
 the hair, for it always appears in isolated patches, and 
 the denuded spots are left clean and polished, and of a 
 marble whiteness. Although it may begin in the head, 
 it commits strange vagaries, inasmuch as it moves about, 
 leaving a spot in the whiskers bare, and passing on to 
 the eyebrows, where another spot is denuded. The pro- 
 gress of alopecia is frequently rapid, and occurs in 
 children and adults ; if among the former, it often 
 attacks the greater portion of a school, and this most un- 
 doubtedly arises from aggregation, sleeping in the same 
 noxious air, and partaking of a diet that is, probably, 
 not sufficiently nourishing, Alopecia, like ringworm, 
 is an evidence of lowered vitality, when the cutaneous 
 surface very readily proves to be a congenial soil for the 
 growth of a parasitic vegetation. The fungus known as 
 microsporon audouini is said to produce the disease ; the 
 light-grey crusts that cover places deprived of hair are 
 often covered with fungoid threads or spores. 
 
 I give as shortly as possible the microscopical results 
 obtained from the examination of twelve patients suffer- 
 ing from alopecia. 
 
SUPPOSED PAKASITIC ORIGIN. 49 
 
 Case 1. Alopecia general ; the hair near bulb found 
 covered with threads, niycelia, which appeared to pene- 
 trate below the surface. 
 
 Case 2. Alopecia circumscripta. Baldness of por- 
 tions of the scalp and face ; hair examined from the 
 whisker, and small crusts extending to cheek. In the 
 masses of epithelial scales and hairs, fungoid filaments 
 were found, and portions of shaft of hairs covered 
 with spores and threads. 
 
 Case 3. Circumscribed alopecia of the scalp. Hair 
 with mycelia standing out from shaft ; the hair itself 
 contained more colouring matter than usual, of a dark 
 brown colour. 
 
 Case 4. Alopecia of the whole of scalp and greater 
 part of body. The few hairs extracted were distorted, 
 broken, and devoid of pigment ; nevertheless, a few 
 tufts of spores were grouped in portions of the hair. 
 
 Case 5. Alopecia confined to the head and face. 
 The few straggling hairs were entirely deprived of 
 colouring matter, but depolarizing light ; sporules and 
 broken mycelia were found. 
 
 Case 6. Alopecia circumscripta. Bald patches, more 
 particularly confined to occiput, and extending to the 
 ears ; hairs very stumpy and devoid of colouring matter ; 
 surface striations obliterated by the spores and filamen- 
 tous material. 
 
 Case 7. Alopecia circumscripta. Bald patches nu- 
 merous over scalp; hair covered with fungus growth, 
 standing out erect from the shaft ; nearly all colouring 
 matter absent. A second examination of this case made 
 three months after treatment by tonics, chiefly arsenic ; 
 the hair it was noticed had regained its healthy charac- 
 ter, and no spores or mycelia could be discovered. 
 
 Case 8. Alopecia circumscripta. Three distinct bald 
 patches about scalp ; the rest of hair profuse; no vege- 
 table growth visible. 
 
50 . SKIN DISEASES OF A 
 
 Case 9, Alopecia syphilitica. Hair presenting a 
 peculiar appearance from having a second or outside 
 casing of epithelium covering a portion of the shaft : no 
 spores or threads of fungus were found. 
 
 Case 10. Alopecia circumscripta. Several bald 
 spots and grey patches throughout the scalp ; hair dis- 
 torted and deprived of colouring matter ; a quantity of 
 epithelium scales surrounded the shaft, but no vegetable 
 growth. 
 
 Case 11. Alopecia circumscripta. Baldness confined 
 to the head ; hair broken and dirty, giving it a dark- 
 brown colour ; many of the broken hairs were covered 
 by spores and mycelium. 
 
 Case 12. Alopecia complete. Nearly every part of 
 the body denuded of hair, a few eyelashes remaining ; no 
 fungoid growth, although the patient seemed to be rather 
 afraid of water. In the course of a few months a con- 
 siderable improvement took place ; a new growth of hair 
 appeared under the arsenical treatment and the appli- 
 cation of a stimulating ointment. 
 
 Summary. In eight of these cases it will be noticed 
 a vegetable fungus was found ; while in the other four, 
 one of which was associated with syphilis, no fungoid 
 growth was detected. 
 
 Although alopecia can be readily cured in young 
 persons indeed is susceptible of a spontaneous cure- 
 it is often obstinately persistent in the adult. Arsenic 
 is certainly one of the most efficient remedies, and in 
 most of my cases its use has been attended with excel- 
 lent results. 
 
 SYCOSIS MENTI. Syn. Mentagra. Tinea sycosis. 
 (Microsporan mentagrophytes, fig. 12.) 
 
 I make no attempt to observe the order or arrange- 
 ment usually adopted by dermatologists ; this is indeed 
 
SUPPOSED PARASITIC ORIGIN. 51 
 
 quite unnecessary, as I am exclusively dealing with 
 parasitic diseases. I therefore proceed to notice sycosis 
 menti, and chiefly so from the fact that this affection of 
 the skin derives importance from the observations of M. 
 Gruby, who first described a cryptogam growing among 
 the crusts in the beard, and which he not only looked 
 upon as a new species, but as a contagious mentagra. 
 
 Willan describes sycosis as "an eruption of inflamed 
 but not very hard tubercles, occurring on the bearded 
 portion of the face and on the scalp in adults, usually 
 clustering together in irregular patches." He thinks, 
 with Celsus, that it may be divided into two kinds 
 Sycosis menti^ which attacks the bearded portions of the 
 face, and Sycosis capiUities, chiefly confined to the scalp. 
 The disease commences slowly ; at first, small red pim- 
 ples are seen about the chin and in the beard ; these 
 gradually increase, and, running together, break, and 
 a yellowish watery discharge exuding, mats the hairs ; 
 in a short time the pustules increase, coalesce and 
 form crusts that much resemble the inside of a fig ; 
 and from this circumstance it derives its name. The 
 disease is inclined to become chronic, and attack 
 other portions of the body, especially those parts freely 
 supplied with sebaceous glands. It is known also to 
 attack the eyelids and cheeks of females as well as males. 
 Patients not unfrequently apply at the Eye Hospital for 
 advice ; the eyes and skin being simultaneously affected. 
 In such cases, iron and cod-liver oil are invaluable 
 remedies, especially when combined with change of air 
 and a good wholesome diet. 
 
 Sycosis is admitted to be a constitutional affection ; 
 even a neglected dyspepsia will greatly aggravate or pro- 
 long the disease, and therefore local applications are 
 rarely of any use ; and this is the best evidence that the 
 parasitic fungus is not the cause of the disease. The 
 glandular structure of the skin is an important element 
 
 D 2 
 
52 SKIN DISEASES OF A 
 
 in modifying and changing the aspect of the disease. 
 M. Gruby believes that it is solely due to the ravages of 
 M. Mentagropliytes ; this fungus forms a sheath round 
 the roots of the hair, and its spores are produced beneath 
 the epidermis, and that both filaments and spores are 
 decidedly larger than those of the microsporon furfur. 
 This, in my opinion, is a very doubtful statement. I 
 made microscopical examinations of specimens taken 
 from six well-marked cases of sycosis, in all of which 
 the hairs were broken and twisted by the mycelia and 
 spores, mixed up in the dark, yellowish scabs, and matted 
 together. In one or two instances the fungus and epi- 
 thelial scales formed a kind of beaded surface over the 
 shaft of the hair ; but in no instance did either mycelia 
 or spores penetrate the cuticle. The discharge from 
 a recent scab was seen to consist of fatty matter, pus- 
 like cells, a few blood corpuscles, and altered epithelial 
 scales. .Gruby attaches too much importance to the size 
 of the spores, as indicating a species. I regard size as 
 a thing of no importance whatever in a vegetable growth ; 
 this, as I have shown, entirely depends upon age, soil, &c. 
 
 PITYRIASIS VERSICOLOR. Syn. Chloasma. Pityriasis lutea. 
 (Microsporon furfur. Fig. 11.) 
 
 Pityriasis is classed by Willan among squamous affec- 
 tions. Squama, a scale, " a lamina of morbid cuticle, 
 hard, thickened, whitish and opaque," is the descrip- 
 tion given of the disease by this physician. The 
 laminae are very thin compared with the eruption, and 
 the incrustations formed after the pustules burst and 
 run together. Frequently a fine mealy or scaly des- 
 quamation takes place, and the epithelium scales freely 
 drop off when the skin is rubbed to relieve the irrita- 
 tion which accompanies the affection. Pityriasis is 
 essentially a disease arising out of a deranged or low 
 
SUPPOSED PARASITIC ORIGIN. 53 
 
 state of health, although some dermatologists look upon 
 it as " a superficial chronic inflammation of the skin." 
 Mr. Hunt always described two varieties of the disease, 
 one contagious and local, the other non-contagious and 
 constitutional. The former is the least common, and 
 may be distinguished from the latter by " the borders 
 of the patches being more distinctly shaded off, and 
 more irregularly diffused/' 
 
 Microscopical examinations of seventeen specimens 
 of this disease, taken from as many patients, gave me 
 the following results : in all, spores and mycelium of 
 a fungus were found. Erichstadt, in 1846, first detected 
 evidences of a fungoid growth in connection with pity- 
 riasis versicolor; and he described at the same time 
 spores piled up in groups or heaps, and mycelia pene- 
 trating the skin ; and, looking upon this as the cause of 
 the disease, it was named microsporon furfur. Robin 
 has not been able to satisfy himself of the identity of this 
 species, or of the grouping of the spores as a particular 
 characteristic. I, however, saw in several cases this 
 grouping of the spores ; while, in others, the matting 
 together of the hairs by the discharge tended to mix 
 spores and mycelia up in an incongruous mass. In 
 Case 1, Mr. N. in a bad state of health and suffering 
 from phthisis, the patches about the trunk were of a 
 yellow-umber colour, the epithelium scales were large 
 and mixed up in a yellowish discharge, and the hairs 
 were partly covered with clusters of spores. A broken- 
 down state of health was observed in a very large 
 number of the cases ; and when the scales fell off, 
 distinct red patches of the skin marked the spots for a 
 considerable time. The affection is a good deal aggra- 
 vated in those persons who ignore the daily use of the 
 bath, and, as a rule, are afraid of soap and water. 
 Tonics, regular living, good diet, and change of air, will 
 effectually cure the disease. 
 
54 SKIN DISEASES OF A 
 
 PSORIASIS. Dry-tetter. Lepra. Scaly Disease. Fig. 13. 
 
 Psoriasis and Lepra are two names for one and the 
 same disease; the former seems to be employed by 
 authors when the scaly patches are irregularly diffused, 
 and the latter when the patches are more isolated and 
 circumscribed, and present elevated edges, denoting a 
 more active, though a less extensive state of disease. 
 In almost every case, the primary affection is thought 
 to be a chronic inflammation of the dennis, producing 
 a vitiated state of the secretions, and an arrest of 
 function. The eruptive patches in the first instance 
 assume the form of an inflamed elevated ring. 
 
 The disease is met with in young children, and 
 in persons of a fair complexion; it frequently shows 
 itself about the elbows and knees. Psoriasis is called 
 by some dermatologists Lepra alphoides, from the white- 
 ness of the scales. The extent and severity of this 
 squamous affection in certain subjects, has sug- 
 gested a further division into psoriasis guttata, applied 
 to patches which appear as pearly drops on the surface 
 of elevated spots ; and psoriasis inveterata, when the 
 scales assume the form of a hard crust over a great 
 part of the body, and very soon fall off in quantities. 
 The disease then causes a smarting, troublesome state of 
 the surface generally. In all, twenty cases of the various 
 forms of psoriasis and lepra were examined; and in 
 twelve of them spores and threads were found, mixed 
 with epithelium and granular matters ; but in no 
 respect did the fungoid elements appear to differ from 
 those discovered and described as belonging to other 
 Dermatophyta. 
 
 There is yet another well-known variety, Psoriasis 
 syphilitica, first described by Willan as a scaly eruption 
 having a syphilitic origin and presenting a copper- 
 coloured appearance. In psoriasis ophthalmica a patch or 
 
SUPPOSED PARASITIC ORIGIN. 55 
 
 circle extends to the borders of the eyelids, which 
 become swollen, tender, and painful. It frequently 
 encroaches over portions of the conjunctiva, and the 
 pustules produce a large amount of irritation, and as- 
 sume a somewhat obstinate character. This affection 
 is sometimes associated with pityriasis, but is distin- 
 guishable from it by the small and distinct nature of the 
 pustules. That psoriasis is not of local or parasitic 
 origin is proved by the failure of topical applications 
 in its treatment; while, in a short space of time, a 
 course of tonic remedies, even without the use of the 
 bath, always so essential to health and comfort, the 
 disease will be perfectly cured. 
 
 LEPRA VULGARIS. Lepra alphoides. Fig. 14. 
 
 Lepra closely resembles psoriasis ; one is simply a 
 milder form of scaly eruption, and appears in persons of 
 all ages. Mr. Hunt says, " when the patches are round 
 and distinct, and depressed in the centre, I call it lepra ; 
 when not so distinctly circumscribed, then psoriasis." 
 These affections are idiopathic forms of disease, very 
 commonly attacking persons advanced in life age indeed 
 is often a most important factor in skin diseases. 
 In most of the patients from which my specimens for 
 microscopical examination were taken, the scaly erup- 
 tions appeared first as small circumscribed spots, chiefly 
 confined to the arms and legs ; the central portions of 
 each were occupied by whitish scales, while their margins 
 and the surrounding skin were of a pale-pink colour 
 and slightly raised. In five cases, I found spores and 
 mycelia almost identical with those of psoriasis ; while 
 in two, epithelium scales and minute fatty matters only 
 were seen, It is very surprising to see how rapidly 
 patients suffering from lepra improve in health under 
 small doses of arsenic, and simultaneously all fungoid 
 growths disappear. 
 
56 SKIN DISEASES OF A 
 
 ECZEMA. Syn. Vesicular Eruption. Running. 
 Scall. (Fig. 15.) 
 
 Eczema is an eruption attended with severe irritation 
 and itching of the skin. It is described by Willan and 
 Bateman as "an eruption of small vesicles on various 
 parts of the skin, usually crowded together, with little 
 or no inflammation around their base, unattended with 
 fever, and not contagious." This disease is common 
 enough among children during the first and second 
 dentition, and is often associated with eye disease is, 
 indeed, one of the most troublesome cutaneous affections 
 of childhood. It affects many parts of the body, as well 
 as the head, face, and eyes, and the vesicles pour out an 
 irritating fluid which excoriates the surrounding skin ; 
 this, however, soon dries up and scabs over, the colour 
 of which is first a greenish yellow, and afterwards brown ; 
 chaps and fissures succeed, and the epidermis, and fre- 
 quently the deeper structures, become involved in the 
 inflammatory process. The hair is matted together by 
 the discharge, and in four out of six cases examined I 
 observed the spores or mycelia of a fungus. In one, the 
 spores were in masses or minute heaps ; and in another, 
 an epithelial cast, from which the hair had escaped, was 
 surrounded by a filamentous growth that had probably 
 encircled the hair, represented in fig. 15. In a case of 
 eczema leproides, the spores were circular and unusually 
 minute, and the epithelial scales were hypertrophied. 
 
 Some authors divide the affection into an acute and 
 chronic stage, and include under the term eczema various 
 forms of lichen and impetigo. The crusts or scabs of 
 eczema are palpably of a dark-brown colour, while im- 
 petigenous scabs are of a dirty yellow colour. The disease, 
 when confined to a certain portion of the scalp, occasion- 
 ally assumes a dry, scaly appearance, and may then possi- 
 bly be mistaken for psoriasis. It has been attempted to 
 
SUPPOSED PARASITIC ORIGIN. 57 
 
 prove that a gouty diathesis is a proximate cause of 
 eczema. This, however, is not in accord with the 
 experience of dermatologists, who regard the disease 
 as one dependent upon functional or nerve derangement ; 
 and this view explains why it selects certain parts of the 
 body in preference to others, and why injury to a nerve 
 trunk is often followed by herpetic and eczematous erup- 
 tions. The influence of the nerves in cutaneous affections 
 is now an admitted fact ; consequently nervine tonics 
 iron, cod-liver oil, &c. with good diet and open air 
 exercise are most essential and useful in their treat- 
 ment. 
 
 Mr. Erasmus Wilson writes : " All cases of eczema 
 are associated with lowered vitality ; in infancy, invaria- 
 bly with defective nutrition and deficient feeding; in 
 middle life, with mal-assimilation ; and in after life, with 
 mal-assimilation, associated with irritability, waste, and 
 decay; and consequently in its treatment, during the 
 growing periods especially, every cause of exhaustion 
 must be met and treated." He thoroughly believes in 
 the value of iron and arsenic, and drugs that act con- 
 stitutionally, or upon the nervous system. As an external 
 application for the purpose of allaying the irritation of 
 the skin and the troublesome itching, there is nothing 
 better than benzoated oxide of zinc. 
 
 Willan highly extolled coal-tar as an external applica- 
 tion in eczema ; and Bateman wrote of it, in lepra, " the 
 continued application of tar-ointment has effectually 
 cleaned the skin of the patches and restored its texture, 
 even when internal remedies seem to have failed : but 
 the advantage obtained is not always permanent." The 
 Ungt. picis liquidce of the Pharmacopoeia is doubtless an 
 excellent stimulant, and especially adapted to old arid 
 ill-conditioned ulcers. I have seen it, when combined 
 with equal parts of cod-liver oil, effect much good in 
 conjunction with constitutional treatment in eczema and 
 
58 SKIN DISEASES OF A 
 
 other skin affections. Its unpleasant smell and damage 
 to the clothing is much against its employment ; but this 
 may be obviated by applying it at bed-time, and by well 
 dusting the surface with violet powder; or, as Hebra 
 directs, by taking a warm bath an hour or two after its 
 application. Oil of cade is also much employed in the 
 treatment of eczema of the scalp. This oil, when 
 diluted with an equal quantity of oil of almonds, answers 
 well in cases of lichen and psoriasis, as well as in so- 
 called parasitic diseases. Professor Erasmus Wilson 
 employs a lotion composed of equal parts of the oil of 
 cade and spirits of wine, added to six times the quantity 
 of water, as an anti-puriginous lotion. The oil of cade, 
 mixed in equal proportions with the Unguentum Zinci, 
 is very useful as an external application in eczema, 
 after the crusts have been removed by poultices. The 
 ointment may be kept constantly applied to allay the 
 irritation. If, however, there is much redness of the 
 skin, with pain and a burning sensation, the disease is 
 in active condition, and will certainly not bear any of 
 the tar preparations : during this stage, soothing treat- 
 ment, warm baths, mild alteratives, and constitu- 
 tional remedies must be employed. If tar preparations 
 increase rather than allay irritation of the surface, they 
 must not be persevered in. If, on the contrary, the 
 scaling process is actively going on, the stimulating 
 effects of these preparations will be found useful ; but 
 to attempt the cure of idiopathic eczema by the appli- 
 cation of either lotions or ointments, will be found a 
 hopeless task. 
 
 IMPETIGO. Running Tetter. 
 
 This disease, which Willan places among Pustules, is 
 characterised by small pustules with an inflamed base, 
 that burst and run together, and produce scabs. It is 
 
SUPPOSED PARASITIC ORIGIN. 59 
 
 not accompanied by much constitutional disturbance ; 
 nor is it communicable, although it may attack all the 
 children of the family about the same time. Impetigo of 
 the head often proves as troublesome a disease as eczema ; 
 it is as important when it makes its appearance on the 
 scalp, and as difficult to cure. In young children, the 
 eruption is almost confined to the pustular form, which 
 spreads over the head, and produces incrustations. In this 
 form it is usually described as crusta lactea milk crust. At 
 other times, and when the pustules are very small and of a 
 mixed character, vesicular, it is termed impetigo eczema- 
 tosa. If the hair happens to be long, it becomes mixed 
 in the honey-like brownish scabs, and falls off. In such 
 crusts, as well as about the hair, I have repeatedly found 
 fungous spores, epithelium scales, and pus-like cor- 
 puscles. The hair bulbs are not destroyed or in any way 
 affected ; the hair therefore is soon restored. In some 
 cases the incrustations are scattered over the head in 
 small patches ; this form of disease Willan calls porrigo 
 granulata. Impetigo attacks the feeble child during the 
 teething process; it is probably symptomatic of the 
 physiological process of dentition. By far the larger 
 number of cases of this disease are associated with im- 
 perfect nutrition and debility. Poverty, privation, and 
 dirt are among the most frequent predisposing causes ; 
 and tonics the iodide of iron, arsenic, and cod-liver oil 
 with an occasional use of chalybeate aperients, prove 
 to be the most efficient remedies. 
 
 Impetiginous diseases usually run a course, and the 
 fungoid spores and threads found in connection with them 
 must be looked upon as evidences of a neglected state of 
 the skin, and not as a part of the cutaneous affections. 
 Among the poor especially, the difficulty made about 
 washing, and the general neglect of baths, as well as 
 the almost universal application of bread poultices, 
 mouldy frequently when used for the purpose, and por- 
 
60 SKIN DISEASES OF A 
 
 tions of which are allowed to adhere to the scabs, go 
 far to deceive the experienced observer as to the parasitic 
 nature of the disease under investigation. In most cases, 
 soothing applications warm water freely applied in this 
 as well as in other cutaneous affections of children 
 and the use of tonics, with chalybeate medicines, which 
 correct the defect in the blood-making process, will cure 
 the disease. 
 
 HERPES. Dry Tetter. 
 
 Herpes, or dry tetter, is placed by some authors 
 among vesicular diseases ; it was at one time a generic 
 name for a number of cutaneous diseases. I have 
 seen a small herpetic ring on the trunk described 
 as a patch of lepra. A good deal of confusion existed 
 with regard to this disease, for Alibert alludes to a con- 
 tagious form of herpes. It is of great importance to 
 determine whether the disease has a specific syphilitic 
 origin. Squamous affections not unfrequently belong 
 to this category, and are then most difficult to cure 
 seldom indeed cured without the aid of special remedies. 
 The reddish-brown or copper-coloured appearance of 
 the eruption, if associated with syphilis, is very striking. 
 The appearances, taken in connection with the history of 
 the case, generally serve as a guide to a correct diagnosis 
 and treatment. The affection known as herpes zoster is 
 ushered in by a slight feverishness, which lasts probably 
 for a day or two, and is succeeded by lassitude and 
 depression. The regular well-defined eruption often 
 extends round the greater part of the body, and is accom- 
 panied by severe neuralgic pains, which are lasting. 
 In a case some months under treatment before I saw 
 it, the pain was excessive, and the patient found relief 
 only in the constant inhalation of chloroform. Its use 
 
SUPPOSED PARASITIC ORIGIN. 61 
 
 was persisted in, contrary to advice, and until he was 
 almost reduced to death's door, when, after the failure of 
 all other remedies, a cure was effected by the continuous 
 use of the galvanic current. 
 
 Herpes circinatus, Mr. Hunt says, "is occasionally 
 mistaken for Herpes tonsumns, or ringworm, which it 
 resemhles only in the annulated form of its vesicles or 
 papules." Dry-tetter occasionally assumes an epidemic 
 character ; and I have seen evidences of a fungoid growth, 
 spores, and mycelia, in two or three cases submitted 
 to me for examination. 
 
 ICHTHYOSIS. 
 
 Ichthyosis (fish- skin) is included by Willan in squamse. 
 It is occasionally seen as a congenital or transmitted 
 form of disease; the skin is so much thickened that 
 it assumes a horny texture, with a tendency to fall off in 
 large scaly patches ; these are, in appearance, quite dis- 
 tinct from the scales of either psoriasis or lepra. In the 
 specimens which have fallen under my notice, the epi- 
 dermis appeared to be hypertrophied ; the scales were 
 completely condensed and blended together, and it 
 was almost impossible, without soaking for some time in 
 a solution of potash, to separate and render them thin 
 enough for examination under high-powers of the micro- 
 scope. This difficulty appeared to be increased in one 
 or two instances by fungus threads binding the scales 
 more intimately together, weaving them, as it were, into 
 a consolidated mass. 
 
 Vitiligo (veal-skin) is a disease occurring in patches 
 over the surface of the body; the scales fall off and 
 leave a white state of the skin, not unlike veal in appear- 
 ance. The scales are composed of epithelium, firmly 
 held together by a thin watery exudation ; a brown or 
 
62 SKIN DISEASES OF A 
 
 blackish granular matter is sometimes largely mixed up 
 in the masses ; but in no instance were spores or fungoid 
 elements of any kind discovered. 
 
 LICHEN. (Summer-rash, fig. 16.) 
 
 Lichen belongs to Willan's order Papulce; "papulous 
 eruptions characterised by numerous small pimples, ter- 
 minating in scurf, and containing no serous or puru- 
 lent matter; the disease is connected with internal 
 disorders." Bateman says " there is scarcely any limit 
 to the varieties of these papular affections." Lichen 
 simplex, occurring about the arms and neck, and over 
 portions of the scalp, is most frequently met with 
 during spring and summer, when it suddenly makes 
 its appearance, and almost as rapidly disappears. It is 
 common enough in tropical climates. Europeans, when 
 affected with lichen during a residence in India, call it 
 the prickly-heat. 
 
 The disease is sometimes confounded with eczema or 
 psoriasis ; but on examination it is seen that a number of 
 red, dry pimples cover the edges of the patches, and, as 
 a rule, it is found that these pimples are papular in 
 lichen, and vesicular in eczema. Lichen agrius is a form 
 of the disease that attacks the arms of grocers and 
 bakers ; it is also known as " baker's itch," for it is 
 thought that the irritating particles of flour or other 
 substances produce the disease. When lichen assumes 
 a chronic form, I have found fungus spores and filaments 
 of a reddish-brown colour invading the shafts of the 
 hairs, similar indeed to the fungus found in Mentagra. 
 In several cases the cutaneous surface was inflamed and 
 swollen, and the epithelium blended together in a slight 
 pale-coloured fluid discharge. 
 
SUPPOSED PARASITIC ORIGIN. 63 
 
 LUPUS. (The Wolf.} 
 
 Lupus is placed by Willan among Tuber cula, and he 
 regarded it as a slow form of tubercular affection that 
 gradually destroys the skin and surrounding structures, 
 and penetrates to a considerable depth. It is not un- 
 frequently divided into many varieties. Biett, who, it 
 appears, saw a good deal of this affection, described it 
 under three heads that is, according to the seat it 
 appeared to him to occupy. 1st, as " superficial lupus ;" 
 2nd, as " deep-seated lupus ;" and 3rd, as " lupus with 
 hypertrophy." Rayer's description of the disease, how- 
 ever, is both practical and happy. " Lupus," he says, 
 " is a chronic cutaneous inflammation, which usually 
 appears in the shape of external tubercules of different 
 sizes, singly or in clusters, of a livid colour, and indolent 
 character, followed either by ichorous and phagedenic 
 ulcers, which become covered with brownish and usually 
 very adherent scabs lupus exedens ; or by extensive 
 changes in the structure of the skin, but without preli- 
 minary or consecutive ulceration lupus non exedens." 
 
 Lupus exedens is, as its name implies, an ulcerating 
 disease of the phagedenic kind, showing no spontaneous 
 tendency to healing, or to the restoration of the affected 
 parts. It most frequently ulcerates deeply without 
 spreading rapidly in a lateral direction ; in other cases, 
 it spreads superficially, just destroying the cutis, leaving 
 the subcutaneous tissue untouched, but extending its 
 ravages laterally in all directions. " Whenever a young 
 person complains of a sore spot within the ala of the 
 nose, or on the septum, or exhibits an adherent scab of 
 ever so small dimensions, situated on the top or side of 
 the nose, or on the lip, surrounded by a base of a livid 
 colour, a close examination should be at once instituted 
 and carefully treated." 
 
64 SKIN DISEASES OP A 
 
 It is by no means uncommon to see patients suffer- 
 ing from this terrible disease at the Eye Hospital. The 
 lower eyelid is very frequently the seat of the affec- 
 tion, and its destruction is almost certain. The eye is at 
 times attacked by chronic inflammation ; the conjunctiva, 
 especially that part covering the palpebral surface, is 
 very much thickened ; the cornea loses its vitality 
 and becomes opaque ; and the upper eyelid droops from 
 paralysis of its motor structures. In one or two 
 instances, and when seen at an early stage, I have 
 attempted to arrest the further progress of the disease 
 by removing the affected surface, but without success ; 
 the phagedena has continued its destructive course. 
 When lupus attacks the face, the ulcerating surface is 
 covered by dirty-looking scabs, which desquamate and 
 reform, until by deeper excavations of the subcutaneous 
 tissues the alse of the nose is exposed, and even portions 
 of the bone. The whole of the face, and a part of the 
 neck, in a female patient of about forty years of age now 
 under treatment, is completely denuded of skin, and 
 the lower eyelids are eaten away. 
 
 I have made microscopical examinations of the pro- 
 ducts of eight cases of lupus exedens (lupus, with phage- 
 denic ulceration), and three of lupus non-exedens ; in two 
 only I discovered evidences of fungoid spores, mixed 
 with epithelial scales, fat and pus-corpuscles, and dark- 
 looking granular bodies. The pus-like discharge poured 
 out is essentially of a scrofulous character ; in some cases 
 it is a serous-looking fluid, with white cells, irregular in 
 form (probably white blood-cells), arid containing nuclei, 
 and largely mixed with granular matters ; a relatively 
 large proportion of fat is found in every specimen, and 
 it appears that the disease leads to degeneration pro- 
 bably disintegration of the fat and sebaceous follicles ; 
 the glandular structures are, therefore, constantly throw- 
 ing off their contents. The surrounding tissues are deeply 
 
SUPPOSED PARASITIC ORIGIN. 65 
 
 involved in the destructive process, which is brought 
 about by a disease of the nerves, and probably an inflam- 
 mation of the cutaneous structures, from " derangement 
 of those forces which regulate the nutritive processes." 
 It is not uncommon to find lupus attributed to hereditary 
 or contracted syphilis. I have not been able to trace it 
 to a specific origin, and therefore find it aggravated by a 
 resort to mercurials. The prognosis in all cases is un- 
 favourable, although, in my friend Mr. Hunt's practice, I 
 have seen cases in which the disease has been arrested by 
 building up the general health, and by employing cod- 
 liver oil internally. In some cases arsenic is a specific 
 indeed the disease yields to medicine, without any 
 topical application whatever ; whereas a single case has 
 never been cured by the employment of escharotics. 
 Arsenic in such cases is no doubt a valuable remedy; 
 but whether its action is purely catalytic, or whether it 
 consists in disturbing and overcoming abnormal changes 
 in the tissues, is difficult to determine. 
 
 Lupus is a perfectly different form of disease from that 
 prevalent in tropical countries, and formerly well known 
 in England and throughout many parts of Europe as 
 leprosy. This affection is only now seen when brought 
 to this country by residents or natives of India ; and 
 Dr. Carter believes its extinction in India depends 
 upon rigorous segregation of those suffering from it. 
 "Leprosy," he says, "is one depending upon mal-nutrition 
 as well as upon hereditary transmission. The cutaneous 
 nerves are chiefly and primarily affected in that part of 
 their course between the outer skin and the deep-seated 
 structures ; and all the changes observed in the varying 
 course of the disease may be traced directly or remotely 
 to the characteristic nerve-lesion, which brings about a 
 deposit in the skin as well as in the nerve-trunks, of a 
 firm, translucent, colourless, or pale-reddish material. 
 As regards the conjunctiva, and the mucous membrane 
 
66 SKIN DISEASES OF A 
 
 of the mouth and throat, the blood-vessels and accessory 
 organs are so involved that the tactile corpuscles disappear 
 before other less sentient elements, and the nerve tubules 
 are separated, compressed, emptied of their contents, 
 and eventually broken up as the disease progresses." 
 
 TINEA TARSI. Syn. Ophthalmia tarsi. CILIARY BLE- 
 PHORITIS. Blear-eye, Fig. 17. 
 
 Tinea tarsi is an eruptive disease closely allied and 
 often associated with either psoriasis or eczema. It 
 is regarded also as a porriginous or herpatic affection, 
 one frequently attacking children, when it appears to 
 be the physiological indication of a change brought 
 about during the building up, or growth, of the human 
 frame. It is also an indication of arrested functional 
 activity, produced by some gastro-intestinal irrita- 
 tion. The disease is often confined to the eyelids ; the 
 hyper-secretion of the meibomian follicles becomes a 
 morbid product, and destroys the cilia ; the eyelashes 
 drop out; or a very abundant secretion takes place during 
 sleep that glues the eyelids together, and in the effort 
 made to separate them the cilia are drawn out. The 
 disease is in truth a glandular affection, one much 
 aggravated when follicles and glands are inflamed. 
 The tear outlet is obstructed by the conjunctivitis, and 
 this leads to disease of the lachrymal gland ; or, if the 
 discharge is not carried away fast enough, the duct is 
 liable to obstruction, the tears also run over, and the 
 cheeks are excoriated. At a later period, the edges of 
 the eyelids are covered over by dark-looking pustules 
 and scabs, in which, among the children of the poor, 
 pediculi are sometimes found. 
 
 In the chronic form of the disease a thickening and 
 
SUPPOSED PARASITIC ORIGIN. 67 
 
 turning down of the eyelids completes the miserable 
 picture : the patient is then said to be blear-eyed. 
 
 Tinea tarsi shows itself in an inordinate proportion 
 of the cases in the out-patient department of the Royal 
 Wesminster Ophthalmic Hospital. A vast number of 
 poor children from the dirty over-crowded dwellings of 
 St. Giles's are always under treatment. Another class of 
 sufferers are those who habitually indulge in strong 
 drinks and eat unwholesome food. It is also a sequence 
 of eruptive fevers, measles, scarlatina, &c. and difficult 
 to cure. Tonics, cod -liver oil, good food, and cleanli- 
 ness, are the remedies chiefly to be relied upon. 
 
 On submitting to microscopical examination several 
 specimens taken from scabs and the pustular dis- 
 charges about the eyes of seven patients, in two of which 
 eczema of the face also existed, I found in four 
 cases spores and filaments, epithelium scales and pus- 
 like granules. In two, small bodies were discovered 
 exactly like the spores of puccinia favi of Ardsten 
 (shown in fig. 1). These spores, it should be noticed, are 
 also frequently floating about in the air of towns and in 
 the country. The bean crops are often infested by the 
 same fungus, when the spores can be collected in any 
 quantities. Tinea tarsi is occasionally associated with a 
 pustular conjunctivitis. 
 
 PUSTULAR CONJUNCTIVITIS. 
 
 Pustular Conjunctivitis. The conjunctiva or white- 
 skin covering of the eye is a delicate transition structure, 
 ranging between the mucous membrane of the true 
 skin and the epidermis, and it very frequently shares in 
 affections of the cutaneous surface. Children crowded 
 together in ill-ventilated bed-rooms, in school hospitals, 
 
68 SKIN DISEASES OF A 
 
 refuges for the destitute, &c. suffer in a remarkable 
 degree from pustular disease of the eyes. From the 
 contagious nature of the disease, it is believed to be 
 propagated by germs* 
 
 The conjunctiva first assumes a red or livid look ; the 
 eyes water incessantly ; minute vesicles form on the skin 
 lining the lids ; sago-like bodies are seen if the lids are 
 turned down ; and the eye is painful and irritable when 
 exposed to the light. A very copious discharge of a 
 whitish matter soon sets in, and minute pustules 
 sometimes form near the margin of the cornea; the 
 disease, if neglected, quickly proves destructive to the 
 transparent covering of the eye. The disease can nearly 
 always be traced to bad air, defective means of ventila- 
 tion, and over-crowding ; the want of a proper amount of 
 nourishing diet always aggravates it. It is, therefore, 
 more common among the children of the poor, and is 
 often endemic in pauper schools, "school hospitals," 
 
 * Dr. Beale believes that when germinal matter has its powers of 
 growth perverted or degraded, it may obtain the power of indefinite 
 multiplication, like the pus of an abscess, or the secretion from puru- 
 lent ophthalmia. Such pus that is, such degraded germinal matter 
 has the power of independent growth under various conditions, 
 and is capable of maintaining its vitality for long periods, if not com- 
 pletely deprived of moisture. When introduced into another animal 
 body, offering favourable conditions, it increases and multiplies. It 
 would appear, therefore, that the growth of ill-conditioned germinal 
 matter may be accompanied by the development of poison in the 
 organism that supports it ; just as the growth of mould changes the 
 quality of bread, or cheese, or other substance, on and in which it ia 
 found. Dr. Beale, however, does not assume the existence of spores or 
 other bodies, whose presence he has not yet discovered, but appeals 
 rather to the germinal matter the existence and growth of which he 
 says he has demons! rated; and although he does not look for the ex- 
 tinction of all contagious diseases, yet he does expect that much good 
 will be derived from keeping the body in an unsusceptible state by 
 living in good and pure air, by dryness and plenty of sunlight, and es- 
 pecially by general cleanliness, as preventives of these forms of disease. 
 Medical Times and Gazette, 1866. 
 
SUPPOSED PARASITIC ORIGIN. 69 
 
 and places where large numbers of children are aggre- 
 gated together. 
 
 A government pauper school, built at an enormous 
 cost to the county, may always be looked upon as a 
 focus of infection for eye and skin diseases. I have 
 constantly under treatment at the Ophthalmic Hospital 
 boys from the Refuge and Ragged Schools. It appears 
 that on the first introduction of boys taken from the 
 streets, ophthalmia, as it is called, breaks out, and affects 
 one new comer after another. The greater part of these 
 boys are brought from wretched homes, half starved, and 
 in rags, and for the first time made clean and fed on 
 wholesome food ; notwithstanding all this, the children 
 become affected with a destructive form of ophthalmia, 
 and for a time fall into bad health. The explanation 
 seems to be that children are destined for an out-door 
 life with plenty of exercise ; the moment they are taken 
 from the gutter and cooped up, aggregated in school 
 hospitals and imposing structures, and limited to a 
 given space, made to breathe the same air, or re- 
 breathe that already deprived of its oxygen and loaded 
 with carbonic acid, and the exhalations of hundreds of 
 other children, then the blood, insufficiently oxygenated, 
 loses its vitality, and the nervous system becomes de- 
 pressed, and ultimately they fall an easy prey to diseases 
 of the skin and eye. 
 
 Years ago* I warned those who were bent upon 
 building palatial pauper schools that failure would be sure 
 to follow. Those at the head of the Poor Law system of 
 the country, and in the face of an array of facts brought 
 to their notice at the time when the danger to health 
 and morals by herding children together under one 
 roof was under discussion, refused to listen to the voice 
 
 * See numerous letters and articles on this question in Examiner 
 and Observer newspapers, 1868 and 1869. 
 
70 SKIN DISEASES OF A 
 
 of reason and common sense. A trial asked for a Scotch 
 boarding-out system, which had already been demon- 
 strated to be healthier for children, as well as more 
 economical for the country, was scouted. The school 
 at Hanwell, said to be a success, was shown by the 
 Medical Reports of 1869 to be suffering greatly from 
 ophthalmia indeed, just then the disease prevailed to 
 an alarming extent ; 70 per cent, of the children were 
 affected, while not more than 22 per cent, in workhouses 
 with less cubic space suffered a proof positive that this 
 affection is propagated and fostered in over-crowded 
 school and sleeping rooms. No costly means of venti- 
 lation prevents disease spreading in buildings of which 
 the boast is that 400 cubic feet and more is allowed to 
 each child, play-grounds covered with Yorkshire flags, 
 the equal of which is not to be found in any private 
 school in the kingdom, and where the cost of maintaining 
 children is above 20 a year per head, a sum that would 
 keep half as many more if the Scotch boarding-out 
 system were followed a system moreover known to 
 prevent " sore eyes and eruptions of the skin among 
 children." 
 
 Miss Nightingale truly says " Children are, as it is 
 well known, the very touchstone the live tests of sani- 
 tary conditions ; and but too often the dying and dead 
 tests of insanitary." This is as true of the insani- 
 tary, imposing architectural " school hospitals/' as it is 
 of the underground dwellings of the poor. Both are 
 examples of the neglect of hygienic arrangements, a 
 vitiated state of the atmosphere from accumulations of 
 animal matters, and the deadly carbonic oxide. Grown- 
 up people frequently suffer from similar causes. A re- 
 markable confirmation of this fact is recorded by M. 
 Huss, who says, among the Lapps of North Sweden 
 ophthalmia is endemic, and it is due to the over-crowd- 
 ing in- door life adopted during the winter months, 
 
SUPPOSED PARASITIC ORIGIN. 71 
 
 when the greater part of the poor inhabitants are 
 cooped up in a close, foul atmosphere, in huts, where 
 there is no escape for the smoke even, except through a 
 small hole in the roof. Most of these people, children 
 and adults, therefore suffer from eye disease, which 
 cannot be cured before the open months of the year 
 set in, and they turn out into fresh air and light to 
 pursue their usual occupations of fishing, &c. So pre- 
 valent is ophthalmia among the inhabitants, that scarcely 
 an old Lapp will be seen without blear-eyes or granular 
 lids. 
 
 The treatment of this disease may be almost surmised 
 from what has already been stated about its cause; indeed 
 the cure is at once simple and efficacious. Affected 
 children must be separated as far as possible both by 
 day and night; daily exercised in the open air, and 
 put upon a diet of meat, eggs, milk, and vegetables, 
 without stimulants. To allay the troublesome irritation, 
 and remove all discharge, a weak, astringent solution 
 must be applied to the eyes, and full doses of iron or 
 ammonia and bark administered two or three times a 
 day. Under no circumstances must children suffering 
 from eye affections be permitted to use the same wash- 
 hand basin or towel. 
 
 There is a peculiar variety of pustular disease of the 
 conjunctiva, about which I must say a few words it is 
 usually associated with variola, or small-pox ophthalmia 
 variola. In this affection, one or more pustules are seen 
 on the eyeball and on the eyelid, and, if neglected 
 or overlooked, will often end in ulceration, prolapse of 
 the iris, and destruction of sight. During the sup- 
 purative stage of small-pox, it is difficult to make out 
 the mischief going on beneath closed and swollen lids. 
 In one or two cases I have met with the spores of a fun- 
 gus ; these, I believe, must have been conveyed to the eye 
 in the lotion or dressing. Ophthalmia fungosa and Sarcosi 
 
72 SKIN DISEASES OF A 
 
 bulbi have been described as fungoid diseases of the outer 
 skin of the eye ; but as they are in no way associated with 
 a vegetable growth or fungus, this is clearly an error. 
 It was, indeed, an egregious blunder of former days to 
 describe " loose-looking textures " growing from the 
 surface of the eye and other situations, as " a fungoid 
 growth ;" such growths bear no resemblance to a pro- 
 duct of the vegetable kingdom, and it is very misleading 
 to continue the use of a term which conveys neither 
 the character nor nature of the growth. A similar 
 objection may be taken to the retention of the term 
 herpes iris, in describing a disease which may appear in 
 the form of a concentric ring over a part of the body as 
 well as the eye. 
 
 DIPHTHERITIC CONJUNCTIVITIS. 
 
 Diphtheritic Conjunctivitis is another affection of the 
 skin of the eye, in connection with which I have 
 found the spores of oidium albicans. Diphtheritic con- 
 junctivitis, although commonly enough met with in 
 Germany, where it is said to occur both as a sporadic 
 and as an epidemic affection, is rarely seen in this coun- 
 try. Out of some three or four thousand patients who 
 annually come under my notice at the Royal Westminster 
 Ophthalmic Hospital, certainly the average must be less 
 than one in a thousand suffering from this disease. 
 Those who have had opportunities of observing its course 
 will agree that it is most intractable to manage, and very 
 destructive to the tissues of the eye even more so than 
 was the famous Egyptian ophthalmia of the Peninsula. 
 By reason of its rarity and its rapidly fatal character, 
 I trust a short account of one or two cases will not 
 prove devoid of interest. 
 
 In the early part of 1870, I was requested by my 
 
SUPPOSED PARASITIC ORIGIN. 73 
 
 friend, Dr. Ridsdale, to see, in consultation with him, 
 
 the child of Mr. M , a fine boy about fourteen 
 
 months old, who had been suffering for some days from 
 a severe attack of catarrhal conjunctivitis. The parents 
 were somewhat unusually alarmed about their child's 
 condition, and this I found arose from the circumstance 
 that their eldest boy, some three or four years before, 
 had lost the sight of both eyes. The discharge from 
 the boy's eyes was excessive, and the attack a smart one ; 
 but in about eight or ten days he made a fair recovery. 
 During the autumn of the year, I was once more sum- 
 moned to see the little fellow, suffering, it was supposed, 
 from a return of the disease. His general health was 
 not so good as on the former occasion; the mother 
 attributed this to teething and want of sleep, and the 
 symptoms of the affection seemed to be greatly aggra- 
 vated. On the second day, a dense white membrane 
 covered both cornese, and quite obscured the pupils from 
 view. I saw at once that we had a case of diphtheritic 
 conjunctivitis to deal with. Every kind of local appli- 
 cation and internal remedy was successively tried, but in 
 vain. A dense membrane reformed day after day ; and 
 first one cornea and then the other sloughed away. At 
 the end of about three months the disease began to wear 
 itself out ; and by careful nursing and good feeding the 
 boy gradually regained his health, and was as happy and 
 playful as a blind child could be. 
 
 In the spring of the year 1872, diphtheria ap- 
 peared in the neighbourhood of Mr. M 's residence 
 
 as an epidemic visitant. Soon after, the eldest blind boy 
 complained of sore throat ; in a few days this proved to 
 be tracheal diphtheria, and in less than a week he was 
 dead. The youngest boy was next seized, and in an 
 equally short space of time he also died. One or two of 
 the girls of the family were similarly affected, but made 
 good recoveries. More careful inquiries about the eldest 
 
 B 
 
74 SKIN DISEASES OF A 
 
 boy's first illness inclined me to think diphtheritic con- 
 junctivitis was also the cause of his loss of sight. The 
 predisposition evinced by the males of the family to take 
 the infection of diphtheria was certainly very remarkable. 
 None of the children, the mother assured me, ever 
 suffered from an attack of croup ; both parents enjoyed 
 an average amount of good health. Several micro- 
 scopical examinations of the diphtheritic exudation 
 were made throughout the attack. Now, I find con- 
 siderable differences of opinion prevailing on the general 
 and special characters of the diphtheric membrane, and 
 also on its histological morbid anatomy. Many com- 
 petent observers, both in this country and on the 
 continent, maintain that diphtheria and croup are sepa- 
 rated by "clinical tradition" only; that "the false 
 membrane found in one differs in no important particular 
 from that of the other and allied diseases." This is quite 
 an erroneous view, as I have shown. (The Lancet, 
 March 15th, 1873.) On teasing out a small portion of 
 the dense membrane to fit it for microscopical examina- 
 tion, under a low power (100 diameters), the normal 
 tissues appear to be replaced by a dense network of 
 fibrous tissue. A power of 350 diameters reveals an 
 aggregation of granular matters, nucleated epithelium, 
 fat-molecules, and minute crystals, closely packed and 
 held together by interspersed bands of connective tissue ; 
 muco-purulent corpuscles entangling foreign bodies 
 and spores of the oidium albicans, as represented in the 
 accompanying wood-cut. The membrane is, in short, a 
 laminated fibroid mass of the superficial and deeper- 
 seated structures. In a later stage, the glandular struc- 
 tures and denser coats of the eye are involved in an 
 ulcerative destruction. That the mucous membrane is 
 affected by the infiltration as well as the more superficial 
 structures, is evident from the loss of sensibility in nerve 
 fibre. Virchow is also of opinion that an exudation takes 
 
SUPPOSED PARASITIC ORIGIN. 
 
 75 
 
 place into the substance of the mucous membrane, and 
 that this produces tension, and subsequently ulceration. 
 
 Microscopical appearance of a Diptheritic membrane. 
 
 Vertical section cut from the dried specimen, showing a, dense 
 fibrous or connective tissue and condensed epithelium cells ; 6, teased 
 out fibrous tissue ; c, involuntary muscular fibres; d, oidium albicans ; 
 e, separated and shrunken pavement epithelium cells. 
 
 E 2 
 
76 SKIN DISEASES OF A 
 
 SPILUS. A Mole. 
 
 Spilus is a kind of nsevus or mole, classed by Willan 
 among macula, a spot. Two cases were subjected to a mi- 
 croscopical examination. Case 1. Dark-brown moles 
 about the clavicular and cervical regions, prominent, and 
 increasing in size, were removed from a child four years 
 old. Hairs protruded from the peculiar-looking dark 
 masses chiefly composed of epithelium and minute granu- 
 lar bodies; but nothing like a fungus was seen. Case 2. 
 Numerous moles of a small size were removed from the 
 shoulder and axilla of a female child five years old, dark- 
 coloured, and rapidly increasing in size. Among the 
 dark-coloured masses fine hairs projected, which were 
 surrounded by threads of a dark fungoid growth, with a 
 few spores. The greater part of the structure, however, 
 consisted of epithelium scales. 
 
 MOLLUSCUM. 
 
 Molluscum, a dark-coloured superficial growth, that 
 shows itself in parts where sebaceous follicles abound. 
 It is frequently seen about the nose, eyelids, and certain 
 parts of the face and neck, and is supposed by some to 
 be of a contagious character, and is termed in consequence 
 molluscum contagiosun. It is also believed that this is due 
 to the growth of a parasitic fungus. I have examined 
 several of these growths without discovering a trace of a 
 spore ; and therefore, if a fungus has at any time been 
 observed, it must have been an accidental introduction, 
 having no share in causing the disease. 
 
 So with regard to similar horny-looking growths of 
 the eyelid, and in which some observers have detected 
 the spores of a puccinia. It is quite certain that the 
 
SUPPOSED PARASITIC ORIGIN. 77 
 
 fungoid elements had nothing whatever to do with this 
 superficial affection ; the disease is simply an exaggerated 
 epithelial outgrowth a piling up of the outer layer of 
 scales. In a case which came under my care at the 
 Royal Westminster Ophthalmic Hospital a report of 
 which, accompanied by a drawing, will be found in 
 the Pathological Society's Trans., 1871, p. 349 the 
 erectile horny growth increased to a considerable size, 
 upwards of an inch and a half in length. A careful 
 microscopical examination showed its composition to be 
 condensed epithelium cells, a thick muco-purulent secre- 
 tion, and layers of connective tissue, without a particle 
 of a fungoid or parasitic growth. 
 
 MYCETOMA. Madura or Fungus-foot Disease of India. 
 
 It is alleged that the spores and threads of a fungus 
 penetrate the superficial and deeper seated structures of 
 the foot and hand, and cause the disease mycetoma, 
 fungus-foot of India. Dr. H. V. Carter was the first to 
 discover the disease, and he described three varieties of 
 the fungoid growth. In the first, the fungus occurs in the 
 form of large globular masses, black externally, brown 
 within, and having a radiating appearance on making a 
 section. In the second variety, the fungus is always in 
 the form of small particles, lighter coloured, and com- 
 posed of threads, and round or oval cells, mixed up with 
 granular matter and oil globules ; or the masses may be 
 pink in colour, and made up of minute beaded fibres, 
 which have the appearance of fishroe-like bodies. 
 The third variety principally consists of light-brownish 
 granules, in a crystaline fatty envelope, whose structure 
 is a miniature condensed form of the black fungus first 
 described. 
 
78 SKIN DISEASES OF A 
 
 I have had the opportunity of examining three speci- 
 mens of the Madura or fungus-foot, one of which, and the 
 last examined, was taken from a foot in an early stage of 
 disease ; and in this, after some difficulty, I found little 
 nests of soot-like balls, of a very minute form, of fungus 
 threads ; in another specimen, I failed to convince 
 myself that the disease was in any way due to the pre- 
 sence of the small amount of fungus mixed up in portions 
 of the structure. My observations were recorded, with 
 drawings of the microscopical appearances, in " The 
 Monthly Microscopical Journal," vol. ii, p. 61, 1871 ; and 
 also in "The Medical Times and Gazette," July, 1871, 
 page 93. The conclusion I formed of the nature of the 
 disease differed somewhat from that of Dr. Carter, 
 inasmuch as I look upon it as a neuroses, a blood affec- 
 tion caused by disease of the nerves of the part, and 
 brought about by mal-nutrition or hereditary trans- 
 mission. The latter is something more than a surmise ; 
 it is borne out by the fact that the disease is pretty 
 much confined to certain districts. That the cutaneous 
 nerves are either primarily or secondarily affected is 
 certain ; the course the disease takes proves this. A 
 contraction of the smaller arteries leads to an arrest 
 of the proper supply of blood to the nerve tissue, and 
 permits of an easy disintegration of the cutaneous struc- 
 tures by the spores and mycelial threads of a fungus. 
 
 A number of specimens of the foot have been seen 
 and examined in this country, and Dr. Carter's descrip- 
 tion of the disease and its histological and pathological 
 characteristics have been generally accepted. It ap- 
 pears, however, that occasionally specimens have failed to 
 satisfy those into whose hands they have fallen of 
 the fungoid character of the disease. Dr. Carter speaks 
 of such a specimen as a variety with "numerous 
 rounded bodies of a structureless or finely granular 
 appearance, in which the fungoid particles are free from 
 
SUPPOSED PARASITIC ORIGIN. 79 
 
 crystaline fringe, and showing a cellular structure, the 
 true nature of which is degenerate fungi.' " * A speci- 
 men of this variety appears to have perplexed Dr. Bal- 
 lingall, as well as the late eminent microscopist, Professor 
 Quekett, both of whom were in consequence unable to 
 satisfy themselves of the fungoid nature of the disease. 
 
 At the end of the year 1869, a foot of the same kind 
 came into my possession for examination ; and I must 
 admit I was a little surprised and somewhat disappointed, 
 after a carefully conducted examination, to be obliged to 
 say it presented no proof that this unusual form of 
 disease was due to the growth and destructive ravages 
 of a fungus. 
 
 The naked-eye appearances of the fungus-foot were 
 as follows : The foot was greatly enlarged and swollen, 
 with numerous excrescences, fungoid-looking bodies, dis- 
 tributed over the upper part, none on the lower. At 
 first sight these might have been thought to communi- 
 cate with the internal structures ; but on attempting to 
 pass a probe through the centre of any one of them, it 
 could not be made to penetrate more than a short dis- 
 tance ; and I doubt very much whether there could have 
 been any actual sinuses leading to the bones during any 
 stage of the disease. The hardening nature of the 
 methylated spirit in which the specimen was preserved 
 may, however, have had something to do with their 
 obliteration. On making a vertical section of the foot, 
 much confusion of parts existed, so that the muscular, 
 fibrous, and connective tissue, as well as the vessels, 
 seemed to be blended in a semi-gelatinous mass. On 
 removing portions of the bony mass, most of the com- 
 pact tissue of which had evidently been absorbed, the can- 
 cellated interspaces were found occupied by numerous 
 
 * Transactions, Bombay Med. and Surg. Society 1860-62, and 
 Medico-Chirurgical Review, vol. i, 1863, etc. 
 
80 SKIN DISEASES OP A 
 
 whitish compact bodies, somewhat resembling millet 
 seeds. These bodies, which Dr. Carter says are of a pink 
 colour in the fresh loot, were apparently mixed up with 
 some crystaline material; but fatty matter so predo- 
 minated, that it was almost impossible to free any section 
 from it without resorting to boiling in ether and liquor 
 potassaa. When boiling in the latter was resorted to, 
 nearly all the fatty mass was held in solution, the residue 
 being a very small quantity of connective or fibrous 
 tissue. A greater portion of the bony mass also dis- 
 appeared when treated in the same way. On the other 
 hand, when the spores and mycelia of a fungus were 
 subjected to a similar process, sufficient remained behind 
 to enable any one to recognise the species, and without 
 difficulty. The spores of fungi seemingly resist the 
 action of boiling fluids, as they do prolonged and intense 
 cold. We are therefore under no apprehension of losing 
 all trace of them while subjecting animal matter to the 
 crucial test of boiling in a destructive reagent. A pro- 
 longed microscopical examination yielded only negative 
 results with regard to fungi. The cells and fibres which 
 Dr. Carter says " are imbedded in black masses of mat- 
 ter" could nowhere be found; neither could any of 
 " the fishroe-like substance made up of defaced fun- 
 gous structure " be seen. 
 
 The papillae were hypertrophied and mostly struc- 
 tureless ; nothing like fibrous tissue or a capillary loop 
 could be made out, even in sections from the sole of the 
 foot. The epithelial and other layers were so blended, 
 that not a perfectly-formed nucleated cell could be 
 obtained. The pigment, generally so abundant in the 
 skin of the black race of human beings, was nearly all 
 removed. Portions of the sub-filamentous material 
 occasionally presented an appearance somewhat resem- 
 bling ciliated epithelium. These were readily broken 
 down, and floated about in a mass of granular particles, 
 
SUPPOSED PARASITIC ORIGIN. 81 
 
 without nuclei, and only slightly fibrillated. Fat cor- 
 puscles abounded, either free or massed in cells, in some 
 of which were seen groups of smaller corpuscles, giving 
 a false appearance of nucleated cells. The subcutaneous 
 infiltration of oily particles, and the disintegration of the 
 various tissues, gave to all the specimens placed under 
 the microscope a confused resemblance ; and although 
 some few bodies of a " spindle shape !> were seen, it is 
 impossible to conceive that they were either " ciliated 
 epithelium," " degenerate fungi," or the altered forms of 
 " a true oidium," the material contents of the branching 
 tubular canals of which have become altered through 
 some kind of natural quiescence or encystment." If such 
 encystinent had taken place in this instance, it had 
 become a complete disguise of all known fungoid charac- 
 teristics ; and under such a disguise it was not at all 
 surprising that the late Professor Quekett should fail to 
 come to any " definite opinion of its character." 
 
 In a more recent specimen sent to this country, I 
 found decided evidences of algoid filaments. In this 
 foot the sinuses were of a considerable size, and, 
 when examined from within outwards, present a some- 
 what funnel-shaped appearance, but rather leading from 
 than into the bones of the foot. The destruction of the 
 small bones of the foot was curiously complete the 
 compact tissue being wholly removed, leaving behind 
 only the open spongy portion, in the interior of which 
 large and small nodulated masses of black matter, which, 
 when fractured, looked like crystalline masses of stearine, 
 mixed with the colouring matter of the blood. Sections 
 of these bodies presented no evidence whatever of fungoid 
 growth ; and, although in a few other specimens in a 
 semi-fluid condition flocculent filaments were found, I 
 may fairly say that the small quantity of algoid matter 
 mixed in any specimen examined was sadly out of pro- 
 portion to the rest of the disorganised matter. Oily 
 
82 SKIN DISEASES OF A 
 
 particles, blended with fibrous and connective tissues, and 
 often crystaline bodies in indescribable confusion, were 
 the rule; while in a few instances semi-transparent 
 yellowish scales of a more definite character were occa- 
 sionally seen, blended with the fatty and granular par- 
 ticles. A portion of the black mass taken from the 
 interior of a bone proved to be an exceedingly intract- 
 able substance. I submitted it first to the action of 
 boiling alcohol and ether, neither of which reagents 
 affected in any way the colouring matter or crystaline 
 substance. Benzole, hydrochloric acid, and liquor 
 potassse were tried in succession, with a negative result. 
 Boiling in sulphuric acid converted a small nodule into 
 a bituminous liquid ; but on the addition of water it was 
 immediately precipitated in the form of scales. Hot 
 nitric acid completely dissolved a mass with effer- 
 vescence, giving off at the same time fumes of nitrous 
 oxide, leaving only a perfectly clear yellowish solution 
 behind. Fragments placed in a platinum spoon, and 
 brought to a blow-pipe heat by a Bunsen burner, burned 
 with a bright flame, and whilst so burning gave off a 
 peculiarly pungent odour, leaving behind an exceedingly 
 minute portion of whitish ash. 
 
 The attempted destruction of fungoid matter by the 
 same reagents is not nearly so complete ; and not until 
 after long boiling in nitric acid is all trace of spores and 
 mycelia lost. An excellent chemist and microscopist, at 
 my request, submitted a portion of the mass to a chemi- 
 cal analysis, and found it to consist of fatty matter, 
 phosphates of iron and lime, a little carbonate of lime, 
 and a small quantity of an organic substance albumen 
 not a particle of a fungus.* In one or two specimens 
 
 * The chemical composition of these masses resembles very closely 
 the white stony concretions submitted to Gmelin, in 1821, by Tiedemann, 
 who discovered them in the muscles of a man who died from the com- 
 
SUPPOSED PARASITIC ORIGIN. 83 
 
 I noticed the spores of a puccinia " a vegetable para- 
 site " as well as minute fragments of vegetable tissue 
 cellulose which probably might have been accident- 
 ally introduced. 
 
 The Rev. Mr. Berkeley believes " there is not the 
 slightest ground for supposing that the disease depends 
 on inoculation with the spores of the true parasitic fungi 
 belonging to the rusts and mildews ;" * and certainly a 
 rather unusual view of the way in which the fungus 
 spores enter through the sinuses is taken; for in this 
 special specimen of diseased foot they presented the ap- 
 pearance of having been bored out by an animal rather 
 than a vegetable parasite. But, admitting the sinuses to 
 be either small or large, do they not in every case indi- 
 cate a pre-existing state of disease, and of a very grave 
 character ? Another point of scarcely less moment is 
 the less frequent variety of diseased foot that is, the 
 foot in which " degenerate fungi with numerous rounded 
 bodies " are the chief elements of destruction an earlier 
 or more advanced stage of the disease than that in which 
 fishroe-like bodies are found ? Since in the first the 
 fungi must have passed into a degenerate state, it cer- 
 tainly should be a more advanced stage that is, so far 
 as ordinary appearances and facts assist us in arriving at 
 an opinion. The destruction of the various tissues in 
 
 bined effects of brandy, dropsy, and gout. Gmelin found them to con- 
 sist of 73 parts of phosphate of lime, with a trace of iron, 7 parts of 
 carbonate of lime, and 20 parts of animal matter similar to albumen or 
 fibrine. Tiedemann believed them to have resulted from the violent 
 attacks of gout : but this guess proved to be only a step in a later 
 discovery made by Hilton and Owen that these " concretions " were a 
 species of hydatid -and which the latter observer, in 1823, proved to be 
 the cysts of the dreaded trichina spiralis, and that the supposed concre- 
 tions were due to the calcification of the cysts after the death of the 
 spiralis worm. 
 
 * Rev. S. M. Berkeley * On the Fungus-foot of India." Intellectual 
 Observer, vol. ii, page 248. 1863. 
 
84 SKIN DISEASES OF A 
 
 the first specimen of foot is certainly not greater than in 
 those in which the mycelia of a fungus have been found. 
 
 The eminent mycologist, Mr. Berkeley, accepts the 
 hypothesis of the fungus-foot disease, describes the 
 fungus as a new species, and assigns to it a new name ; 
 and although " the fungus resembles closely the genus 
 mucor," he nevertheless prefers to place it with chionyphe, 
 a species " only found under snow," and concludes that 
 " it is highly probable that many of our common moulds 
 commence with a similar condition. The first indication 
 of a change in tainted meat is seen to commence with 
 little gelatinous spots of vegetation of various colours, 
 the early stage of some curious species of aspergillus or 
 penicillium." Hospital gangrene may, he thinks, also 
 depend upon a similar cause. I think evidence is 
 wanting in support of such a "probability," which is 
 really no nearer the truth than the many guesses that 
 have been made at a germ theory of disease. 
 
 To establish the fungoid origin of the diseased foot, 
 it is absolutely necessary to show that the spores of a 
 vegetable fungus can penetrate the healthy structures of 
 an animal body during life ; there germinate and destroy, 
 one after the other, the fibrous, cartilaginous, and bone 
 tissues, and ultimately kill the patient. The character of 
 the tissues with which we have to deal seem to make 
 this impossible; and the writer referred to has mis- 
 givings on the point, for he says : " The little granular 
 bodies are so closely involved in stearine, that their ger- 
 mination is scarcely probable." The general symptoms 
 are, in my opinion, inconclusive and unpronoimced in 
 favour of fungus. " The foot swells up, is of a dark 
 colour, numerous sinuses appear, with pink stains or 
 streaks, which penetrate the subjacent tissues, and end 
 in spherical groups of bright orange-coloured particles. 
 The sinuses are more or less lengthy and tortuous, and 
 will not usually yield to pressure of the probe," &c. 
 
SUPPOSED PARASITIC ORIGIN. 85 
 
 Nevertheless, it is expected that the soft yielding spores 
 of a fungus will find their way through these tortuous 
 sinuses, passing along in an opposite direction to a strong 
 outward flow of sanious discharge, the usual accompani- 
 ment of such a condition of disease. It is not believed 
 that the sporules, although minute enough, could enter 
 through the circulation a more generally stated opinion, 
 and an equally probable mode of conveying the contagion 
 to the internal parts of the body. The endemic charac- 
 ter of the disease would be more easily accounted for in 
 this hypothesis, as it occurs often in districts where the 
 growing crops of rice are at times devastated by " smut," 
 once thought to be the cause of cholera. But it could 
 not be believed to enter through the blood, because in 
 such a case it would be impossible to understand why 
 the spores of a fungus should select a hand or a foot, 
 and find in either a more congenial soil than in any other 
 part of the human frame ; or why one foot should be 
 destroyed and the other escape ; why the poison should 
 stop at the part where the bones of the leg join the foot, 
 and so forth. 
 
 The incubation of the disease demands a passing 
 notice, as, according to Dr. Carter, it more frequently 
 affects the agricultural classes, men in the vigour of life, 
 and is not associated with constitutional causes, is not 
 known to be transmitted ergo, since agricultural 
 labourers go about barefooted, and seldom wash their 
 feet thoroughly, it is thought that the spores of a fungus 
 will penetrate the very hard skin, and produce " worse 
 ravages than the dreaded guinea-worm." Although I 
 can easily understand how the guinea-worm makes its way 
 through the skin of a native, particularly when softened 
 by standing in water, I cannot see how the spores of 
 a fungus should be capable of exerting the same force 
 as an animal parasite provided with a mouth and jaws, 
 and a pre ordained desire to provide itself with a lodging 
 
86 SKIN DISEASES OP A 
 
 in the leg or foot of the first animal that crosses its 
 path. It must be conceded, also, if the disease origi- 
 nates in a fungoid growth, there should be no instance 
 of a foot that does not bear some evidence of the 
 characteristic poison. Such a specimen as I have de- 
 scribed, without a particle of fungus, places the hypo- 
 thesis of a fungoid disease in a serious dilemma. My 
 objection is in nowise met by saying that this form of 
 diseased foot is exceptional; for, curiously enough, two out 
 of three specimens I have examined present no positive 
 evidence of fungus in any portion of the diseased mass, 
 and the appearances observed scarcely come under the 
 designation of flocculent filaments. 
 
 I will briefly describe the last specimen of fungus- 
 foot disease sent to me by Dr. Blanc, of H.M. Indian 
 Army, surgeon in charge of the Rajkote Hospital. The 
 disease was found to be confined to the sole of the foot ; 
 it occurred in an unusually young person, a native, of 18 
 years of age, who had previously enjoyed good health ; 
 in whom, soon after coming into hospital, mycetoma was 
 diagnosed by Dr. Blanc, who, on submitting a very small 
 piece, which came away in a poultice, to microscopical exa- 
 mination, observed well-defined filaments of a fungus. 
 The affected part of the sole of the foot was immediately 
 excised, the wound rapidly healed, and in a short time 
 after the patient was able to leave the hospital. 
 
 The specimen, preserved in strong spirits of wine, 
 presented a hardened, shrunken appearance when it 
 came into my possession. A small cut had already been 
 made across the most prominent discoloured centre of 
 the mass. This opening I enlarged for the purpose of 
 removing small portions for microscopical examination ; 
 and finding nothing but quantities of fat-corpuscles and 
 connective tissue, I dissected away a good deal of the 
 surrounding structures, and came down upon two or 
 three blackish-looking minute spots. With a low power, 
 
SUPPOSED PARASITIC ORIGIN. 87 
 
 an inch and a half, and condensed light, I made out a 
 group of globular bodies, exactly like balls of soot, or 
 one of the Smuts of the LFstilaginous species. On re- 
 moving some of these small concretions, which proved 
 to be too intractable for further microscopical examina- 
 tion, I placed them in a test-tube, covered them with 
 liquor potasses, and subjected them for a few minutes to 
 a boiling heat. A small amount only of the colouring 
 matter was dissolved out ; but soon fragments were, how- 
 ever, soft enough to break up on a glass slide. A drop 
 of glycerine solution was then added, and a thin glass 
 cover placed over all. With a power of 350 diameters, 
 I first observed numerous detached fragments of an 
 orange-coloured resinous substance, a number of fat- 
 globules and discoid bodies, with granular matter. On 
 carefully focussing and illuminating the specimen by 
 direct light, articulated filaments were seen imbedded, 
 and slightly projecting beyond the edge of the coloured 
 mass. When more magnified these were converted into 
 free loops, not unlike papillae. The fungus threads were 
 for the most part exceedingly minute ; there was a com- 
 pressed or fossilized appearance about them, if I may 
 so express it. 
 
 On increasing the magnifying power to 650 diameters, 
 these threads were resolved into long, jointed, dissepi- 
 mented cells ; some branching out and attaining to a con- 
 siderable length, while others terminated in an enlarged 
 ovoid head, probably a spore receptacle, containing one 
 or more spores. In others, again, a minute oil-globule 
 apparently occupied the centre ; but it is not easy to 
 determine this point, from the large quantity of colour- 
 ing matter present. A peculiar budding out was noticed 
 in some of the globose cells, and a few bodies separated 
 away from the coloured mass were of a paler colour, and 
 partaking of an amoeboid form, These latter somewhat 
 reminded me of Haeckel's Leptocytode, from the cytode 
 
88 SKIN DISEASES OF A 
 
 of which this histologist says : " a homogenous membrane 
 is differentiated from the granular contents ; prolonga- 
 tions are thrust out, and ultimately become a free-moving 
 body, a Protamoeba primativa." The walls of the filaments 
 appear in some instances thick, while those which were 
 separated from the homogeneous matter were exceedingly 
 thin and. transparent. Notwithstanding the boiling in 
 liquor potassse, large quantities of fat-granules continued 
 to float about, and the carbonaceous colouring matter 
 was not nearly removed. The growth in some particu- 
 lars, save that of colour, appears to partake more of the 
 nature of a confervoid plant in its simple articulated 
 threads and cell multiplication, than of a "truffle-like 
 fungus." But as " one swallow does not make a summer," 
 neither does one examination enable one to write or speak 
 with much authority on fungi. I should prefer, in all 
 examinations of the lower forms of life, to see a hundred 
 examples of the same organisms present before asserting 
 anything decidedly about them. I must again repeat 
 that, so far as I am able to draw a conclusion from the 
 specimens of the fungus-foot I have examined, and, con- 
 sidering the relatively small proportion the fungoid 
 filaments bear to the diseased mass, the fungus must only 
 be regarded as a secondary product ; one which may 
 aggravate disease, but can hardly originate it. 
 
 In the case just described, the spores of a fungus may 
 have been forced into the sole of the foot when the 
 young man struck it against the sharp stone, as already 
 stated, and cut it. The cut healed up, although 
 in about six months it became very painful, and an 
 abscess subsequently formed. Poultices were applied, in 
 one of which a small blackish body was noticed ; and this, 
 upon microscopical examination, proved to be fungus. It 
 is, therefore, probable that spores or the filaments of a 
 Leptotrix, parasitic smut, found its way into the wound 
 at the moment the first accident occurred. 
 
SUPPOSED PARASITIC ORIGIN. 89 
 
 After a careful examination of all the facts, I am 
 bound to consider that the foot disease of India appears 
 to commence in an error of nutrition ; phlegmonous in- 
 flammation and diffuse suppuration follow, and spread 
 from one tissue to another. Specific blood-poisoning, 
 hypertrophy, and increased cell-development, soon pass 
 into complete disintegration of tissue, vessels, nerves, 
 &c. The process of retrogression, at first slow, proceeds 
 to rapid destruction, and soon the albuminoid, oleaginous, 
 and crystaline constituents are blended in an incon- 
 gruous mass. The fatty matters assume, in connection 
 with the flattened connective-tissue cells, an angular, a 
 spindle, or even a mulberry shape. It is obvious that 
 the colouring matter of the nodulated masses must be 
 derived from the iron of the blood ; and sanious fluid, 
 with fat, stearine, and phosphatic matters, blend into the 
 carbonaceous masses " fishroe-like bodies " which are 
 seen to fill the cavities of the bones. The slow disin- 
 tegration of the various structures in the Madura foot- 
 disease is no doubt greatly exaggerated by the ordinary 
 effects of a tropical climate, often an important factor in 
 disease, and one well exemplified in those remarkable 
 forms, elephantiasis and leprosy, both of which seem 
 to originate in an error of nutrition, brought about 
 by arrest or destruction of the nerve fibre, and ending 
 in a complete metamorphosis of all the structures. 
 
 To summarize the conclusions to which I have been 
 led, from the various observations, examinations, and 
 experiments, it appears almost beyond a doubt that there 
 exists but one essential organism, a fungus whose spores 
 find a soil common alike to the surface and the more 
 secluded parts of the human or animal body; that 
 variations in skin diseases, associated with a parasitic 
 growth, are due to differences in the constitution of the 
 person affected; to the moisture, exudation, soil, and 
 temperature under which the development of the fungus 
 
90 A FUNGOID OK GERM 
 
 takes place. Consequently it is neither correct nor desi- 
 rable to separate and classify them as "parasitic diseases 
 of the skin." That parasitic growths vary but little in 
 any case, and then only in degree, not in kind, some 
 soils appearing to be better suited than others for their 
 development, that furnished by the eruptive or secreting 
 surface being in every way the most congenial ; while 
 diversity of form in all cases arises from growth taking 
 place either upon a sickly plant, a saccharine solution, 
 or an animal tissue. That fungi generally excite chemical 
 decomposition in the soils on which they feed ; and it is 
 the exclusive province of a certain class, when spread on 
 the surface of an albuminoid, saccharine or alcoholic, or 
 slightly acid liquid, to develope and grow, and during 
 growth to give rise to either the alcoholic, acetic, or 
 putrefactive fermentation.* 
 
 A FUNGOID OR ORGANIC GERM THEORY OF CHOLERA 
 
 AND OTHER DISEASES. 
 
 A fungoid theory of disease, of the zymotic, epidemic, 
 and endemic forms especially, has been proposed, and 
 
 * " Numerous facts justify the belief that there exists but one essen- 
 tial fungus, whose sporules find a soil for development and growth upon 
 the surface, or even within more secluded portions of the human body, 
 and that varieties in the growth of the fungus are due to differences in 
 the constitution of the individual, to the moisture, exudation, soil, or 
 temperature under which the development of the fungus takes place. 
 It excites a chemical decomposition in the pabulum on which it feeds, 
 and the different stages in its growth give rise to alcoholic, acid, and 
 putrefactive fermentation. Of the latter there is ample evidence in 
 many of the parasitic skin diseases, and especially in favus, the odour 
 of which closely resembles that of some methylamine compound. 
 (Lowe.) Thus, their irritant action may very soon establish an erup- 
 tion." Aitkens Science and Practice of Medicine, vol. ii, p. 179. 2nd 
 edition. 
 
THEORY OF CHOLERA. 91 
 
 surrounded by endless speculations, some of which it 
 is said explain satisfactorily the cause of thes^. affec- 
 tions, their mode of incubation, and contagious nature. 
 From the position occupied by the advocates of the 
 theory, rather than any other cause, it has in a measure 
 taken possession of the public mind ; and while the pro- 
 fession may appear partially agreed as to there being a 
 specific poison for some forms of disease, it is divided 
 upon what may be described in two words as the " vital 
 germ theory" and the " physical theory " of disease. 
 
 Those who hold fast to a fungoid or germ theory, 
 believe that the poison takes the form of living vegetable 
 organisms, which are rapidly developed, and capable of 
 exciting, under special conditions, either fermentative or 
 putrefactive changes in bodies ; and without them there 
 is no fermentation, no putrefaction ; and that under 
 certain circumstances these are poisons, and act as 
 such, and are the exciting cause of zymotic diseases 
 in the animal body. But, in defining the processes set 
 up by these germs, and accounting for certain symptoms 
 relating to these diseases, the theory fails to explain how 
 a disease so readily communicable as scarlet-fever is 
 more frequent before ten years of age, and why there is 
 immunity from a recurrence of this fever, or small-pox ; 
 why selective in respect to season ; why the majority of 
 those affected recover and for the most part recover as 
 it were spontaneously ; or why, when a person is infected, 
 there should be recovery at all ? A number of similar 
 questions suggest themselves, and I have here presented 
 only those that seem to me to remain unanswered by the 
 advocates of a germ or fungoid theory of disease. 
 
 With regard to the " physical theory," the advocates 
 of which believe that while the organic elements are 
 poisonous and colloid in structure, that they are capable 
 of being transmitted as solid matters in water or air, and 
 at the same time are destructible. Their action on the 
 
92 A FUNGOID OR GERM 
 
 animal body is said to be purely physical, and the advo- 
 cates of this theory wisely decline to offer any decided 
 opinion upon the changes brought about, whether of a 
 fermentative or putrefactive character. 
 
 I endeavoured at one time to trace the history of the 
 fungoid or germ theory of cholera ; and in a paper read 
 before the Medical Society of London, March, 1870, and 
 also in papers contributed to the Medical Times and 
 G-azette of the same year, the results were duly chronicled. 
 
 Dr. Tytler, I believe, was the first to connect cholera 
 with diseased food, during an epidemic visitation at 
 Jessore, in 1817. He asserted that it was occasioned by 
 the consumption of unsound rice. But when, in 1833, 
 he exhibited his specimens to the Medical Society of 
 London, they proved to be " ergoted rice." Now, 
 although rice infected with ergot has been known to 
 produce fearful results, the symptoms of poisoning differ 
 widely from those of cholera. In 1861, a gentleman lost 
 six horses in a very sudden and suspicious manner. His 
 belief was that they had been poisoned, and a veterinary 
 surgeon agreed in this; but, upon making a careful 
 post-mortem, he could find no trace of poison. The food 
 was then examined, and some oats attracted attention. 
 My friend, Professor Tuson, sent a portion of his 
 supply to me for examination. I noticed that the grains 
 were matted together in lumps, by a sort of cobweb-like 
 material. Upon breaking them up, a blackish-looking 
 powder was deposited on the paper ; placing some of this 
 under the microscope, "bunt" and other spores were 
 detected, and I was able to clear up the mystery, and 
 confirm a suspicion that death was due to a cumulative 
 poison swallowed in large doses in the food, which 
 starved rather than nourished the animals. Numerous 
 well-authenticated instances of a similar kind might be 
 given ; but this is unnecessary. 
 
 Dr. Wallace, of New York, in 1845, endeavoured to 
 
THEORY OF CHOLERA. 93 
 
 connect epidemic disorders generally with fungi ; and Dr. 
 Cowdell, in 1848, published a work entitled " A Disqui- 
 sition on Pestilential Cholera, being an attempt to explain 
 its phenomena, nature, causes, prevention, and treat- 
 ment, by reference to an extrinsic fungus origin." At 
 p. 202, these remarks occur : " The conclusion at which 
 we have arrived as to the nature of the cause of pesti- 
 lential cholera is, that it is a minute fungus, probably 
 resembling the Torula cerevisice." 
 
 Dr. Mitchell, of Philadelphia, in 1848, in a work on 
 the origin of malarious and epidemic fevers, writes : 
 " The cryptogamic theory will well explain the peculiar 
 domestication of different diseases in different regions 
 which have a similar climate' the plague of Egypt, the 
 yellow fever of the Antilles, and the cholera of India. 
 We have only to suppose, what is known to happen in 
 other cases, that the fungi, on which cholera is assumed 
 to depend, acquire at times, as do the germs of some 
 contagious diseases, an unusual power of reproduction 
 and diffusion, and a greater potency of expansion. Such 
 germs may be carried by men, and goods, and ships ; or 
 be scattered by the winds, to regerminate wherever 
 special conditions are found. Thus can we see why the 
 poison prefers the route of streams, or infects the damp 
 parts of cities ; and why classes living in clean apart- 
 ments, in dry districts, suffer so little." 
 
 In this author's writings we find a well-woven hypo- 
 thesis of cholera, one which it appears to be hypercritical 
 to attempt to demolish. It is first necessary to mention 
 the supposed discoveries in the same direction of Drs. 
 Swayne and Brittan, who published (The Lancet, October 
 6, 1849) an account of their examinations of cholera 
 evacuations. After repeated microscopical investigations, 
 these gentlemen convinced themselves that fungoid and 
 other bodies found in the rice-water discharges of cholera 
 patients were characteristic of the disease, What at 
 
94 A FUNGOID OR GERM 
 
 that time was considered more conclusive, Dr. Budd 
 announced that he had succeeded in detecting the same 
 bodies in the water of several districts where cholera 
 prevailed. Here was a wonderful confirmation of the 
 fungoid origin of cholera at last. It so happened, how- 
 ever, that some of the evacuations and specimens were 
 sent to Mr. Busk for examination, and, at a meeting of 
 the Microscopical Soc. Oct. 17, 1849, he demonstrated 
 that the large bodies figured by Dr. Swayne were merely 
 " a species of Uredo, a kind of smut frequently found on 
 wheat," exactly like specimens noticed by this experienced 
 microscopist in a loaf of brown bread purchased the 
 same day at Greenwich. Uredo is not destroyed, as I 
 have said, by boiling in caustic potash, and it readily 
 passes, unaltered, through the intestinal canal. Other 
 bodies, supposed to be peculiar to cholera evacuations, 
 were, at the same time, seen to be starch granules and 
 portions of the cellular structure of the inner coat of 
 the bran of wheat. 
 
 Professor Hallier, a botanical teacher of Jena, on 
 examining the contents of the bowels of patients attacked 
 by cholera during two more recent visitations, believed 
 that he had discovered the active agent or cause of the 
 disease. He detected in the evacuations spores, or seeds, 
 and filaments, or roots, of a fungus. Hallier, like his 
 predecessors in these inquiries, attempted to cultivate 
 these spores, and in due time produced, as he thought, 
 another fungus belonging to the genus O'idium. Con- 
 tinuing to pursue his investigations, he found he could 
 produce from O'idium another fungus, Urocystis, a 
 vegetable parasite. The dark-coloured spores of Uro- 
 cystis are very characteristic, and often infest the 
 leaves of plants, but have never yet been suspected of 
 having any connection with O'idium or " mould ;" nor can 
 it be proved that this fungus attacks the grain of any food 
 plant ; the spores have never been detected on the leaves 
 
THEORY OF CHOLERA. 95 
 
 of the rice plant. Unfortunately, then, for his theory, 
 Hallier assumed too much ; for the entire foundation of 
 it was based on an assumption that moulds are related 
 to UstilagineS) or " smuts and bunts ;" for " moulds," he 
 says, " are mere unripe fruits of Ustilagines" He be- 
 lieved that his so-called " micrococci " travelled with the 
 rice plant from India, and entered the stomachs of per- 
 sons, and destroyed the villi of the intestinal canal with 
 amazing rapidity. Hallier has, however, after mature 
 consideration, seen fit to change his ground a good 
 deal, and now says that he is not convinced that any 
 infectious disease can be caused by spores or fungi per se. 
 He also considers that there are ripe and unripe forms 
 of " moulds ;" and, on occasions even when ripe spores 
 are cultivated on a weak and poor soil, they do not pro- 
 duce " cholera contagium ;" so that, although large 
 quantities of spores may occasionally be swallowed, they 
 may not be retained long enough in the intestinal canal 
 to produce ripe micrococci, and they then pass through 
 inocuously. He further describes micrococci to be 
 particles of a plasmic mass without cell walls, requiring 
 the highest powers of the microscope in skilled hands to 
 detect them. A high temperature, he says, is necessary 
 to maintain these micrococci in an active condition ; and 
 therefore only during warm weather, the summer of 
 European latitudes, could it be expected the fungus 
 would germinate and propagate as in India. Thus driven 
 from his original proposition that cholera is due to the 
 Urocijstis form of fungus, he adopted another which 
 deserves no more confidence at our hands. Indeed, it 
 has been, and can be again, most conclusively shown 
 that diseased rice takes no part whatever in the produc- 
 tion of cholera. Rice is rarely eaten uncooked, either 
 here or in India. It is always boiled, and well boiled, 
 so that anything like vitality or germinating power is 
 probably destroyed. But supposing that spores of any 
 
96 A FUNGOID OR GERM 
 
 kind were found adhering to rice grains, and taken into 
 the stomach, would they remain there long enough to 
 germinate? Certainly not. The spores of the edible 
 mushroom require to be passed through the stomach of 
 the horse ; but, instead of germinating there, they only 
 germinate in the excretions after exposure to a moist 
 air ; and it by no means follows, because the spores of 
 the mushroom may be taken from the dung of the horse 
 and made to vegetate, that a crop of mushrooms could 
 be produced in the intestinal canal of the animal. The 
 notion is preposterous. 
 
 We begin to find out that fungi are curious organisms. 
 The spores of one species will not germinate until they 
 have suffered the probation of the horse's stomach; 
 another species requires to pass through a similar pro- 
 bationary stage in the stomach of another animal. If, 
 however, it should be found that O'idium germinates in 
 the human stomach, and that the intestines are the 
 natural habitat of the fungus, should we not expect to 
 find spores in the excretions of those in health as well 
 as in disease ? At all events we ought to find Hallier's 
 unripe forms of Ustilagines in health as well as disease. 
 
 Experiments such as those made by Hailier upon 
 mice, feeding the animals with bibulous paper steeped in 
 choleraic putrefying evacuations, cannot be accepted as 
 at all conclusive. Dr. Thudichum, upon carefully re- 
 peating them (I quote Dr. Thudichum's experiments 
 rather than my own), found that out of 51 mice 13 only 
 became ill; 11 of these died, 2 recovered, and the 
 remaining 38 were unaffected. The poison was active 
 only between the fourth and tenth days, which is exactly 
 the period when a chemical change is found to take place 
 in the proportions of nitrogen and carbonic acid con- 
 tained in it ; and from this Dr. Thudichum argues that 
 its power for evil depends on the evolution of hydrogen. 
 If the poisoning were caused by fungi, all the animals 
 
THEORY OF CHOLEKA. 97 
 
 should have been infected, or, at all events, there should 
 have been no immunity for any length of time during 
 which choleraic matter was administered. The conclu- 
 sion arrived at by Dr. Thudichum is, that the decompo- 
 sition which takes place is such as might have been 
 expected from the putrefaction or decomposition of 
 albuminous matter by chemical processes, and not by 
 any fungoid fermentation as the action is going on in 
 parts of the body into which fungi have never been 
 alleged by the advocates of the fungoid theory to pene- 
 trate. An examination also of the cholera excreta by 
 the spectroscope negatively confirms this view. It shows 
 that a somewhat complicated alteration of the chemical 
 condition of the blood takes place during the rapid 
 progress of cholera disease. 
 
 I must not omit to notice the more recent researches 
 .on this important question made by Drs. Lewis and 
 Cunningham at the instigation of the Indian Government. 
 Particular attention appears to have been directed by 
 these gentlemen to the changes produced in the blood of 
 cholera patients, as well as " experiments on the in- 
 troduction of organic fluids into the system." The 
 microscopical characters of the blood were observed by 
 means of Strieker's warm stage. " A small drop of blood 
 having been received on the centre of a carefully cleaned 
 covering-glass, the latter was pressed down on the wax 
 cell and hermetically sealed. The cell was deep enough 
 to prevent the blood from coming into contact with the 
 slide, and therefore allowed its free exposure to the in- 
 cluded air." In this state, large numbers of specimens 
 were retained for examination without any danger of the 
 admission of extraneous elements, and a series of re- 
 markable changes in specimens of cholera-blood were 
 noted. For instance : the number of white corpuscles 
 at first visible was small ; but with the widening of the 
 ring of serum a series of phenomena gradually occurred, 
 
 I 
 
98 A FUNGOID OR GERM 
 
 * 
 
 beginning at the close of one hour after the blood 
 had been drawn. These changes are thus described. 
 "Normal-sized white corpuscles began to migrate into 
 the fluid ; but in addition to these, and in far greater 
 numbers and activity, were much larger and more 
 delicate bioplastic bodies ; cells they were not, for they 
 had not at this time the faintest differentiation of wall, 
 contents, or nucleus. They were simply masses of fluid 
 bioplasm bioplasm so fluid and diluted as in many 
 instances to be almost, if not entirely, indistinguishable 
 
 by refraction from the surrounding medium 
 
 Gradually the consistence of these large bioplastic masses 
 appears to increase, and they, as it were, grow into sight. 
 Their movements are extremely constant and free no 
 mere alterations of form, but free progression, along 
 with such movements. The alterations in form vary 
 extremely, sometimes consisting of the emission of 
 rounded and lobulated protrusions, and at others of 
 the running out of elongated slender extensions and 
 threads." Similar bodies may at the same time be seen 
 in the serous spaces of the clot. After a time they 
 begin to divide, and give rise to a second generation of 
 bioplasts, smaller, though scarcely less active. But at 
 the close of twenty-four hours from the commencement 
 of the examination, only a few remain freely mobile; 
 the majority have considerably increased in size, whilst 
 they have also become denser in substance and more 
 full of granules. At this stage they are more or less 
 spherical, and are not at all unlike pus-corpuscles. 
 During all this time, moreover, the serum remains clear 
 and free from all traces of bacteria. The specimen may 
 remain in this condition, comparatively unaltered, for 
 weeks, though the bioplasts in the majority of cases pass 
 on to further changes. 
 
 Other important facts have been made known by 
 these investigations bearing upon the "germ theory" in 
 its application to cholera. In the specimens of blood 
 
THEORY OF CHOLERA. 99 
 
 submitted to immediate investigation, not the faintest 
 trace of bacteria was detected in any instance, although 
 they were carefully searched for under high magnifying 
 powers ; and, as a rule, such organisms were singularly 
 absent from the specimens submitted to continued ob- 
 servation. The authors say, " One of the most impor- 
 tant points determined by these observations is the fact 
 that the blood in cholera is, as an almost invariable rule, 
 free from bacteria, either actual or potential. This is 
 the case as well, shortly after death as during life, and 
 holds in regard to every stage of the disease. In one or 
 two cases a slight development of distinct bacteria has 
 occurred during the course of observations ; but this is 
 no more than may occur in the most healthy specimens 
 of blood (owing most likely to accidental contamination) ; 
 and the idea that bacteria are normally present in the 
 blood in cholera may be finally dismissed.'' With regard 
 to the presence of fungus-germs as a characteristic of 
 the disease, " There is absolutely nothing in favour of 
 any such view ; there is absolutely no evidence of the 
 existence of fungoid elements in the blood whilst in the 
 body, and only very rare and clearly accidental develop- 
 ment of such bodies after its removal from it." 
 
 There seems good reason for believing that the state- 
 ments which have been made concerning the existence of 
 organisms in the blood of cholera-patients, and of per- 
 sons suffering from other acute specific diseases, have 
 been based upon more or less obvious errors. In the 
 first place, mere molecular debris have doubtless often 
 been cited as the so-called " micrococci " of Hallier ; 
 whilst, on the other hand, cultivation-experiments with 
 the view of developing actual or " potential" germs are 
 liable to be vitiated by numerous sources of fallacy, and 
 have given rise to many other erroneous statements.* 
 
 * British Medical Journal, Feb. 22, 1873. 
 
100 A FUNGOID OR GERM 
 
 DUST AND DISEASE. 
 
 "With regard to the sensational cloud of " dust and 
 disease" which an eminent Physicist raised, and thought 
 proved a connection between the minutely divided par- 
 ticles of matters diffused through the atmosphere, and 
 the production of disease. This is a question of some 
 importance ; and before I proceed to discuss it, let me 
 clear the ground of anything having the semblance of an 
 ambiguous meaning, such as is likely to occur by blend- 
 ing together the terms " organic germs " and " organic 
 particles." I am ready to admit that dirt is always 
 floating about in the air of towns in pretty considerable 
 quantities ; but I am not' prepared to look upon this as 
 " organised matter ;" neither can I admit that the two 
 terms are either synonymous or convertible ; for although 
 there are many particles floating about in the atmo- 
 sphere, it has not been proved that " organic germs " (that 
 is, seeds of living organisms, because that is what we 
 understand by this term) at all times and seasons enter 
 largely into the composition of the air we breathe. 
 
 This question has been ably investigated by Dr. 
 Angus Smith, who was long engaged in determining the 
 relative condition of organic and other matters in the 
 air of towns, and its probable effect upon the health of the 
 inhabitants. This chemist and physicist found that the 
 chief cause of the insalubrity of the air of towns consists, 
 not in " organic germs/' but in the emanations from 
 human beings too closely packed together, and the noxious 
 gases generated by coal thrown off by manufactories and 
 the large numbers of dwelling houses. These tend to 
 saturate the air with matters of the most injurious kinds 
 as sulphuretted hydrogen, sulphuric and hydrochloric 
 acids, ammonia, chlorides, and albuminoid matters 
 that are far more injurious to health and life than 
 " organic germs." Dr. A. Smith is bound, therefore, to 
 withhold his assent to anything like an " organic germ " 
 
THEORY OF DISEASE. 101 
 
 theory, because he believes it has not been shown by its 
 advocates to have any relation whatever to disease, and 
 is likely to divert attention from causes far more im- 
 portant. Professor Wanklyn also proved by his ammo- 
 nia process that the total quantity of organic nitrogenous 
 matter passing out of the lungs and held in solution in 
 the form of watery vapour during the space of twenty- 
 four hours in health amounts to about three grains. In 
 disease it increases, and even in health the quantity of 
 free ammonia varies considerably. Dr. Ransome like- 
 wise ascertained that a larger quantity of organic matter 
 is thrown off in Bright's, and some other diseases; 
 while in catarrhs, measles, dipththeria, &c. a great 
 deficiency is noticed. This fact scarcely chimes in with 
 the " organic germ " theorists, who assert that large 
 quantities of albuminoid matter, vibrios, &c. are found 
 in the air-passages in catarrhs and other diseases. 
 
 With regard to the filtration of air through cotton 
 wool, this does no more than arrest the moisture thrown 
 off by the lungs saturated with ammonia and other 
 salts. It is now several years since Professor Tomlinson, 
 of King's College, showed how impossible it is to keep 
 any vessel chemically clean, or even decently free from 
 the dust floating about in a closed-up room. He found 
 that corking up bottles did not prevent the entrance of 
 particles of matter ; and, after many trials to exclude the 
 dirty atmosphere, he tried cotton wool, and found, by 
 placing a pledget of this material quite loosely in the necks 
 of bottles or glass tubes, they remained perfectly clean 
 for many days. This chemist, by employing flasks or 
 bottles thus prepared, was also enabled to delay the 
 crystallisation of saturated solutions of salts to an almost 
 indefinite period. He excluded in this way all particles 
 of inorganic matter which at once form a nucleus of 
 crystallisation; but such particles of matter are easily 
 detected, and are certainly not to be confounded with 
 " organic germs." The members of the medical profes- 
 
102 A FUNGOID OR GERM 
 
 sion have not lagged behind in a matter of this kind ; but, 
 on the contrary, have taken the initiative in the use of 
 cotton wool inhalers for those engaged in deleterious 
 manufactures, and in places where a large amount of 
 organic or mineral matters are given off. Dr. Angus 
 Smith in his report upon the air of mines, 1854, par- 
 ticularly dwells upon the danger to the health of the 
 miner produced by taking into the lungs through the 
 open mouth a large quantity of coal-dust and mineral 
 matters. " If," he observes, " as you approach the 
 entrance of a pit, a gleam of sunlight happen to play 
 across it, 'you will at once perceive an immense quantity 
 of solid matters issuing forth in an endless stream. The 
 impure air of the mine is loaded with these solid par- 
 ticles, which, when caught and submitted to microscopic 
 examination, are found to consist of coal, crystaline 
 bodies, &c. ; and if issuing from iron mines, there are, in 
 addition to those named, tine metallic atoms, products 
 from gunpowder explosions, arsenic in small quantities, 
 and the sulphides of various metals. With a given quan- 
 tity of inspired air, the miner takes into his lungs from 
 sixty to eighty grains of such impurities each day ; so 
 that it will be readily understood that such dust and dirt 
 must in a very short time exert a very injurious effect 
 upon the lungs and other organs of the body." To pre- 
 vent the entrance of such matters into the mouth and 
 lungs, Dr. Smith proposed the use of a simple respirator, 
 made of a layer of cotton wool, placed between wire 
 gauze, which could be made for a few pence. But, after 
 all, these noxious matters bear no proportion to the 
 ordinary condition of the atmosphere. If a larger pro- 
 portion were mixed, the respiratory tract is well taken 
 care of, being freely supplied with cilia, ciliated 
 epithelium, which remain in action, sleeping or waking ; 
 by their agency a sort of churning process is carried on, 
 amply sufficient not only to arrest the further progress 
 of any foreign body, but probably to kill " organic 
 
THEORY OF DISEASE. 103 
 
 germs," and effectually prevent their germination in the 
 internal organs ; and when particles enter in large 
 quantities, additional means are provided for their 
 expulsion by the acts of coughing and sneezing. 
 Much of the foreign matter inhaled collects in the throat, 
 is entangled in the mucous secretion, and expelled by 
 expectoration. 
 
 Those who know little of the microscope and the 
 perfection to which the modern instrument has attained, 
 believe that the germs spoken of in his cloud of dust 
 cannot be seen by its aid, nor appreciated in any way, 
 except by watching their play across the path of a ray of 
 solar or electric light. This is not the fact ; they can be 
 easily taken on glass slides in suspected places, and 
 in a very short time. If I take an ordinary slip of glass, 
 and smear it over with glycerine, and expose it for a 
 moderate space of time either in my room or in the open 
 air, I find, when examined under the microscope, a 
 quantity of small particles deposited thereon, such as 
 articles employed and in domestic use at the moment of 
 exposure would throw off, chiefly consisting of mineral 
 and vegetable substances as fragments of coal, granite, 
 brought in on the dress or shoes from the street, vege- 
 table hairs, cotton, as well as wool fibres detached from 
 the clothing ; these are often mixed with a few starch 
 granules from the bread, and occasionally a few spores 
 of fungi. In the house, the latter form but an inappre- 
 ciable proportion, while in the open air we often take a 
 good deal ; and during the warm damp weather peculiar 
 to some periods of the year, a larger quantity of fungus 
 spores and particles of vegetable hairs will be deposited 
 on the slides. By employing a more scientific method, as 
 by the use of an aspirator, which draws in a larger quan- 
 tity of air in a given time, Pasteur and others collected 
 the same kind of substances. If I put a small quantity 
 of distilled water into the bottle before the air is drawn 
 through by the aspirator, I also find, in the course of a 
 
104 A FUNGOID OR GERM 
 
 few days, some of the lower forms of animal life deve- 
 loped in the fluid. This experiment, it is thought, 
 seems to prove the spontaneous generation theory, hete- 
 rogenesis, of animal life. 
 
 The microscope has clearly demonstrated the nature 
 of these various substances floating in the air ; and it is 
 more than probable that a few escape detection, either 
 from their extreme minuteness or transparency; but 
 those who have investigated the subject will agree with 
 me that it by no means follows that the air is filled with 
 organic particles, or contains more than a very small pro- 
 portion of " organic germs." Dr. Angus Smith deter- 
 mined the relative proportion of organic matter in pure 
 air to be 1 grain in 200,000 cubic inches, while the most 
 impure air of towns contains often as much as 1 grain in 
 8,000 or 10,000 cubic inches of air. But every step in 
 such an inquiry is surrounded by incomprehensible 
 difficulties. We can no more understand these floating 
 germs than we can how the perfume of a flower is diffused 
 through the air, or how a grain of musk should give off 
 its peculiar odour for the space of twenty years, and not 
 become perceptibly diminished in bulk. We are equally 
 unable to explain why, out of twenty persons breathing a 
 loathsome air, one will breathe in a fatal dose, and nine- 
 teen escape the malarious poison. I must confess I do 
 not believe that if the twenty were breathing through 
 cotton wool filters the relative condition of health and 
 disease would in any way be altered. Aristotle found no 
 difficulty in believing, and in inducing others to believe 
 with him, that worms and insects were generated by 
 dead bodies ; and it was only towards the end of the 
 seventeenth century Redi succeeded in demolishing this 
 theory, and proving that worms and insects which appear 
 in decaying bodies are produced from the ova deposited 
 there by the mature parent. It was, however, thought 
 to be altogether preposterous to suppose that putrefac- 
 tion could produce an insect (neither could it), and this 
 
THEORY OF DISEASE. 105 
 
 explanation was at the time utterly rejected as fallacious. 
 Driven from the insect world where such an hypothesis 
 could have no chance of success, the disciples of Aristotle 
 sought refuge in the world of fungoid life, or " organic 
 germs." But here we arrive at an immense gulf, which 
 requires to be bridged over before we arrive at the portal 
 of truth. I have no doubt that the hypothesis of the 
 production of disease by " organic germs " first obtained 
 credence simply because we know of something analo- 
 gous occurring in the flight of insect life, and the propa- 
 gation of swarms which inflict blight on vegetable life. 
 To associate such a phenomenon with the occurrence of 
 disease in animal bodies is most unreasonable and un- 
 satisfactory. From an " organic germ " to a " specific 
 germ " theory seems to be a natural transition ; and cer- 
 tainly the most plausible affiliation of a disease with 
 the " specific germ " theory is cholera ; but even here 
 it is seen that opinions are more and more divided. 
 
 I must say, if we assign a specific germ theory to 
 cholera, we have to deal with a migrating malaria, a 
 wandering cause of disease not confined to hospital, 
 house, or district, capable of being diffused through the 
 atmosphere and conveyed along vast tracts, affecting 
 different places with a varying intensity which no known 
 conditions of atmosphere will explain, but nevertheless 
 possessing the power of reproducing itself, so as to 
 spread the disorder by fresh creations of the original 
 conditions which produce it. Microscopical and che- 
 mical examinations of the atmosphere of the wards of 
 the hospitals in which large numbers of cholera patients 
 have been treated, afford no reliable solution of the 
 question. Mr. Rainey and Dr. Thomson, in 1855, made 
 every attempt to isolate the supposed " cholera conta- 
 gium" in the wards of St. Thomas's during the epidemic 
 visitation of that period, but without success. They 
 only discovered particles of vegetable hairs, coal dust, 
 epidermic scales, starch, with occasionally a few spores 
 
106 A FUNGOID OR GERM 
 
 of fungi ; but the results obtained were thought to be 
 unsatisfactory ; nor did there appear any grounds for a 
 belief that these organic germs had anything to do 
 directly or indirectly with the prevalence of the disease. 
 The remarkable coincidence of the spores of " rusts " 
 and other fungi, noticed by many during the first out- 
 break of rinderpest, led some to suppose that this 
 disease was due to the spores of fungi ; but this opinion 
 was soon exploded. 
 
 Admitting fungi cause cholera, will it explain the sud- 
 denness of the attack ? It is out of character to suppose 
 that a few fungi, more or less, will kill suddenly, or in 
 the course of six or eight hours. If the specific germs 
 lie dormant, and are capable of assuming other forms, 
 then why are they not found in this state prior to the 
 attack, or during a condition of health ? Hitherto all 
 the bodies found during life have been satisfactorily 
 traced to food, or are the natural products of the mucous 
 membrane. What then, may I ask, has positively been 
 made out with regard to the fungoid bodies or organic 
 germs in the production of disease ? The most carefully 
 conducted examinations have as yet produced only ne- 
 gative results. That most common form of disease in 
 which fungoid bodies are found Leptothrix is known 
 to arise from a neglected condition of the mouth and 
 teeth, and is readily cured by a proper use of the tooth- 
 brush. 
 
 Aphthae, thrush, a disease of infancy, is said to 
 be caused by a fungus. It occasionally affects grown 
 people, is chiefly confined to the mouth, and consists of 
 small irregular whitish-looking patches, which are scat- 
 tered over the surface of the mucous membrane. The 
 aphthous patches look at first like particles of curd ; these 
 fall off and leave behind them a reddish, raw-looking 
 surface. Successive crops of aphtha? reform, and, with 
 the addition of fungoid spores and filaments, often prove 
 troublesome and dangerous to the little patient. 
 
THEORY OF DISEASE. 107 
 
 The disease occurs at an early period of life, is sel- 
 dom sean after teething is completed, and the child is 
 able to partake of other food than milk ; it is therefore 
 believed to be produced by the unhealthy condition of 
 this fluid ; or, if the child is brought up by hand, to an 
 improper diet of some sort. In all cases, acidity of the 
 stomach is present ; and this points to the necessity for 
 attention to diet in attempting a cure of the disorder. 
 When thrush occurs in the adult, it denotes a con- 
 siderable amount of debility, and requires the aid of 
 tonics, bark and ammonia, with wine and a nourishing 
 diet, to sustain the strength and restore the health. 
 
 Aphthae are formed on surfaces that are provided 
 with a continuous epidermis, and especially indicate a 
 low condition of the system ; at such a time the fungus, 
 which is the oidium albicans, finds a suitable soil to 
 feed upon, and soon becomes a destructive agent de- 
 manding attention. 
 
 All disease is simply a disturbance of the con- 
 structive and assimilative processes whereby the normal 
 integrity of the animal body is maintained. The cause 
 of jungle-malaria, and fen- ague, may be traced to ac- 
 cumulated and decaying organic matter. By breathing 
 for a given time an atmosphere loaded with sewer and 
 other gases, typhoid fever is produced ; other fevers can 
 be traced to similar causes. Indeed, many diseases 
 classed among zymotic can be accounted for without 
 assuming the existence of germs or spores. The blood 
 in all cases is primarily affected, and when a disinte- 
 grating action is set up in any part of the animal 
 economy, its tendency is downward ; the effect that fol- 
 lows varies only with the histological anatomy of the 
 part. The action is a nearly uniform process of irrita- 
 tion, inflammation, and disintegration, tending towards 
 death. 
 
 I do not therefore deny the probable influence exer- 
 cised by minute organic particles mixing in the air we 
 
108 A FUNGOID THEORY. 
 
 breathe, in the summum malum of human ills ; but what 
 I contend for is, that as yet it has not been demonstrated 
 that such bodies hold any precise relation to any special 
 form of disease. It has, indeed, been repeatedly shown, 
 since Boehm's experiments in 1838, that fungoid bodies 
 are a constant accompaniment of other debris ; and these 
 are found soon after death in abundance throughout the 
 whole extent of the intestinal tract so soon that they 
 actually appear to have grown, or commenced their 
 growth before death. So much remains to be done in 
 this difficult inquiry, and so many doubtful points re- 
 quire clearing up before it can be truly said cholera or 
 any other form of disease has its origin in a fungoid 
 growth, that, if we are not more cautious, we shall find 
 the cholera contagium what Boeck has aptly described it 
 to be " the infusorial chaos of the intestines." 
 
 If any one is determined to furnish a formula for 
 cholera, he may take " bad air, bad water, sewer emana- 
 tions, floating stinks, germs if you please, bad ventila- 
 tion," with perhaps a dozen or two more evils, which 
 are all more or less concerned in originating the disease. 
 But, after all, the prime occasion for its development is a 
 mass of human beings aggregated together, either in 
 towns, in barracks, or the country, into a sufficiently 
 limited area of mud, gravel, granite, large and imposing 
 structures, crowded courts, alleys, cellars in St. Giles's, or 
 attics in Glasgow; and the necessary conditions for 
 cholera as well as other zymotic diseases are provided. 
 A vitiated state of atmosphere breathed and re-breathed 
 until it becomes lung-tainted and poisonous, to which is 
 added bad water, bad food, bad lodging, or some chronic 
 disease assisting to lower the vital functions, and our 
 choleraic catalogue is exhausted. 
 
 J. MALLETT, PRINTER, 59, WARDOUR STREET, SOHO, LONDON.