For my part, I hold that Koch and others have immensely exaggerated the importance to be attached to the fact that the bacillus does not grow in their culture processes below 90°; and that the fact is far too trivial to sustain the weighty conclusion arrived at. When Koch's name shall have lost its hold upon the judgment, and when sober thought shall be directed to this question, a little dry light may suffice to show that the cases between the laboratory and nature are perhaps not parallel. The soils and conditions are certainly not identical, and may be widely dissimilar. A difference in the results of natural and of artificial culture processes, therefore, would be no great marvel. Besides, in the matter of this bacillus, who shall say that the species may not be so differentiated by parasitism in the animal host as to make its restoration to its former (possibly normal) stage of saprophytism more than ordinarily difficult to the pathologist? Outside the laboratory there is a mass of evidence tending to upset the claim made for the true parasitism of the bacillus. From the phenomena connected with the occurrence, the incidence, and the course of consumption, it would appear to be a necessary inference not only that the consumption-plant grows saprophytically on the soils in bedrooms at ordinary temperatures, but that it grows in the open air in some regions. In Australia, for instance, where cattle are not housed, there is no other sufficient explanation of their infection.

Dr. Emmerich's reference, however, to the temperature under floorings, in connection with the bacillus, suggests that the bed may be a suitable place for the artificial cultivation of the vegetation. It does not appear that Koch looked upon the bed as a possible incubator for this bacillus; yet for the third of every day the degree of heat considered absolutely necessary for its growth outside the body is actually present in the upper portion of the mattress on which the future patient lies. As a large amount of moisture is evidently not required by the species (there is always some dampness in a mattress in use), and as a proportion of animal matter will be present in the mattress, the proportion depending on the length of its service, we have here all the conditions required for the growth of the bacillus. And yet it would seem that Koch did not exhaust out this forcing-house for the species before he inferred it to be a true parasite.

One practical suggestion arising out of the bed and I have done with consumption for the present. As in the other diseases that are here supposed to originate in the bedroom, from vegetation occurring

there on soils other than those in the bed and then extending to those soils in the bed, so in consumption it is of the last importance, for similar reasons to those given elsewhere, to change the mattress and paillasse as well as the bedroom.

Many serious maladies crowd to the front to invite some attention, but I can delay no longer now to dilate upon the prospective relief all the peoples of the earth will have from the plagues they have brought down upon themselves in their dormitories-a boundless relief that will be initiated on the introduction of the change in the bedding of the British soldier.

APPENDIX.

1. RÖTHELN,

UNDOUBTEDLY the nearest congener of measles is rötheln. Rötheln is so often associated with measles and resembles the disease so closely in many respects, that the highest authorities have not been able to do more than draw a theoretical line of demarcation between them —a line which frequently fades away and is altogether lost at the bedside.

The confusion in the views of writers as to the precise nature of this exanthem need not be dwelt on. It is clearly enough shown in the Historical Notice of rötheln in Thomas's article in Ziemssen; where, too, the varying accounts of the pathology and symptomatology of the disease are well brought out. The nosological vicissitudes of rötheln are interesting and instructive, and are not yet over. For this protean exanthem, long bandied about between scarlet fever and measles, and regarded by many of the older writers as a mongrel complaint with more or less admixture of one or other, or both, of these diseases, is now formally ranged as a pure-bred specific disease uncrossed by either, and free also from all taint of roseola. Its position, however, is far from being secure; and, indeed, the facts adduced and reasons given by Drs. Willcocks and Carpenter in their paper in The Practitioner1 show conclusively that it is untenable. As these acute observers say :- "Mere dermatological evidence alone cannot be considered a very sound or trustworthy basis on which to erect the fabric of a separate specific disorder :" and if we discard this test, what diognostic signs are left by which to distinguish rötheln from its congeners? Even in the small group of cases they described, Drs. Willcocks and Carpenter found many departures from what is laid down as the normal course of this so-called specific disease. Catarrh and coryza, usually mild, were in some instances "remarkably intense;" in others the cases were sine catarrho. Earache was absent here and present there; slight branny desquamation occurred in most cases, but in others was not seen; and the incubation period was variable. "Some of our cases, again," they say, differed substantially from the ordinary descriptions given of rötheln, and they did not entirely agree among themselves.

1 Notes on a Limited Outbreak of Rötheln, with remarks on the Incubation Period. The Practitioner, September, 1887.

On one very important point there was a curious deviation. "Although several nurses and the house-surgeon were affected by the complaint here described, none of the children who were in the ward at the time, and who were of various ages from two to twelve, contracted it. Yet rötheln has been stated to be highly contagious in the case of children (M'Call Anderson). . . On the whole, a careful review of these cases has led us to think that the facts in favour of rötheln being a specific morbid entity entirely separate from measles are not in all points quite satisfactory, and it seems probable that the evidence on the subject may, to some extent, require reconsideration."

This calm and judicial conclusion is in accord with the views here taken. A large survey of all the phenomena recorded in the history of rötheln will reveal, I submit, that the older theories as to the composite causation of the disease are nearer to the truth than the more modern theory of causation by one specific agent.

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It is easy to see that the great diversity of opinion and the apparent contradictions in the accounts of writers on rötheln come of observations made on the larger epidemics and limited occurrences of different countries, or on those of the same country in different years or at different seasons; and that while the leading features of the various outbreaks will have had a more or less pronounced measly or scarlatinal stamp given to them (when measles or scarlet fever or both have prevailed at the time and near the place of their occurrence), the minor variations in the one outbreak will have been determined, probably, by the purely local conditions of a room, or of a house, or of a small number of houses. Every phenomenon, indeed, connected with rötheln is in perfect harmony with the straw mildew theory." Assuming the soundness of that theory, we have a full explanation of the phenomena. An attack of rötheln is seen to be in effect a morbillous or morbilloid exanthem, generally wanting wholly or partly in some one or other morbillous element, and occasionally having some adventitious element or elements superadded. By the supposition of a variation in the kind of straw used in bedding the substitution, for instance, of rye, or barley, for wheaten straw, or the use of rushes, dried grasses, &c., in place of straw-by the assumption of the complete or partial arrest of growth for the time being of the fungi which induce specific effects on the air-passages, or of the species that cause skin manifestations; and of the greater or less amount of various kinds of organic matter in the bedding or in the bedroom; we have the conditions for large variation in the nature of the vegetation and in the proportion in which each of the contributory forms shall be represented in the sum total of the air-contamination of a room. By an extension of the view, we see that when the disease takes the scarlatinal type some of the elements of the specific vegetation that causes scarlet fever have been added to the morbilloid poison.

Though the question of the cause of scarlet fever must not detain us here, it may be suggested that the frequency with which it over