rooms precluded contamination with straw fungi, or because they slept on flock, or some material on which these fungi do not occur (although, when loaded with organic matter, it may support the vegetation). On these and other grounds wilful infection is an abomination; but the belief that it has ever been the principal means by which an epidemic has been spread, or by which the measures of the hygienist have been frustrated, would seem to rest on a slight foundation.

The ordinary way in which wilful infection is brought about is by putting uninfected children to sleep for a few nights with infected children. This plan of "bundling" them is sometimes reversed, and cases are reported in which it has failed: a result which squares with the "straw mildew theory," but is not to be reconciled with the theory of contagion. One of the most remarkable things, however, in connection with the wilful infection of children with measles is that it should have been resorted to ages ago, and that the necessity for it should still exist, in the opinion of the vulgar of our day. For the introduction of the custom was decidedly hostile to the doctrine of the highly contagious nature of measles; and its regular observance from that time to this is a practical protest against the teaching of the schools.

That a contagion which possesses the diffusible qualities and marvellous potency so confidently assigned to this one of measles by the learned, should nevertheless be found by simple folk to be incapable of infecting their children without the coarse expedient of bedding the healthy with the sick, is so strange that one may wonder how this antagonism between theory and practice should have passed unnoticed. Theoretically, there should be no loophole of escape from infection for children within a certain distance from its living source; practically, parents find they cannot ensure infection unless they leave their children in bed with the infected. Instead of children being smitten with lightning-like rapidity in the presence of the infected, or taking in the virus in a mysterious manner during a visit from a thoughtless, or an unconscientious (or an undisinfected) physician, or from other incautious, ignorant, or

reckless carriers of infection; instead of children "catching" the measles with that astounding facility one would expect from the characteristics given to the ideal or assumed contagium; we find parents driven, in order to effect their infection with certainty, to bring their children into the very closest quarters with the real working contagium. For they have discovered by experience or learnt by tradition that an epidemic may pass their children by, notwithstanding unrestricted intercourse, or intentionally prolonged commingling with the infected during the daytime. In short, they know by rule of thumb that if they would take time by the forelock they must seek infection in the night and in bed.

The inferences to be reached from this conflict between the conclusions drawn from actual observation and the views arrived at by the scientific method are significant, both as to the source of the measles poison and as to the requirement of a much larger dose of the poison than is supposed by the etiologist to be sufficient. The rough procedure of the people says plainly enough that children will not take measles by the absorption of a particle, or of a few particles, or of any number of particles given off from the infected in the day-time, but that they must be shut up for a few nights with the sick; which, being interpreted by the light from the "straw mildew theory," means that they have to get their dose of poison, not at second-hand through the bodies of the infected, but direct from the common cause the paillasse—and that, to get that dose, they must go through their probation on the mildewed bed, and in an atmosphere efficiently contaminated with the "straw fungi."

And what contagionist shall throw a stone at the philosophy of these folk? When these classes see in one epidemic after another that all the resources of science fail to stop measles, that the fair promises held out in prompt isolation an extreme disinfection are a delusion and a snare, what other conclusion can they arrive at than that the health authorities are biting files They are told too, perhaps, that the visitation of the disease has been partly in consequence of their own laches, and that its severity has depended largely on the dirty state of their

habitations; but they can see the injustice and the absurdity of such reproaches. The mechanics and labourers of England are not all filthy, as it is the fashion of some fussy, kindly, wouldbe sanitarians to insist they are. The majority of their dwellings are as clean and tidy and wholesome as they can make them. And their perceptive faculties are not so blunt but they can see that sometimes the most decent families among them suffer severely when the vilest outcasts of the neighbourhood, wallowing in filth, go scot free; and they have quite enough mental capacity to reach the inference that, whatever it is that causes measles, it is not dirt. When, therefore, they sum up the position, and reflect on the strange nature of a contagium which is supposed to be so alarmingly active that the faculty would impound it at once by isolation, but which they find by experience is so inoperative that often it cannot be got to do its work of infection, when given every opportunity short of "bundling," it is no great wonder that these bewildered people should get hold of the notion that there must be something wrong somewhere, or that the more hasty and rebellious spirits should go so far as to question whether the highest authorities know much more about the matter than they do.

CHAPTER XXV.

Straw in bedding the common cause of measles-Removal of the uninfected -Isolation of the infected-Epidemics not stopped in any known instance-The explanation offered is that the common cause has not been suspected or disturbed-Improvement of the present measures futile.

IF we turn now to the view that measles depend upon a common cause in the dwelling, and are not communicated from person to person by contagion, we shall have before us a full explanation of the results of all the means hitherto tried for the suppression or limitation of the disease; we may scan intelligently every instance of private and public local quarantine, and in the occasional instances in which the results have been favourable, we may determine the causes that have brought about these exceptional results; we may apprehend the nature, and estimate the amount, of the danger involved in the popular custom of putting uninfected to sleep with infected children, and the converse; and we may see plainly the principle upon which, and the means by which, measles are to be prevented by private persons at will, and are to be stamped out entirely by civilised nations in time.

The uselessness, speaking generally, of the segregation of measles patients at epidemical seasons consists in leaving the unsuspected sources of their infection undisturbed. Assuming that the main source is in the straw bedding, it will be obvious from what has gone before that the straw in all the beds in a district will, at epidemical seasons, become damp enough to cause the germination of the "straw fungi" sooner or later,

provided that the local conditions of the bedroom do not prohibit the necessary degree of moisture for the germination and growth of the vegetation. The period at which efficient aircontamination (efficient, that is, for the occupant or occupants of given rooms) is reached, will vary therefore in different quarters of a district, in different streets of a town, in different dwellings of a district or town, and even in different rooms of a dwelling. In a small proportion of rooms, when they contain paillasses, the air-contamination will not reach the standard of efficiency even for children, and in most bedrooms the contamination will fall short of being efficient for adolescents and adults under ordinary circumstances-that is, when in health, or when they are not confined to their bedrooms through accident, fevers, parturition, &c.-though the amount of contamination in a large proportion of these rooms would be sufficient to infect children, and, in exceptionally severe and prolonged epidemics, to implicate adults, even for the second or third time.

If we take a mental survey of this (assumed) vast, though not continuous, field of straw mildews growing and ripening in different parts of it at different times, and if we suppose, first, that one form of isolation is carried out at a given part of the field-in a house, say, containing a large family, one or two members of which are infected-and that the uninfected children are sent away to another part of the district, it is easily to be apprehended that their after-infection or exemption will depend simply on whether they are removed to another part of the actual or potential mildew field or not. If by accident they are shifted to a spot where the soil, or the conditions, or both, are inimical to the straw mildews, they will be exempt; but if they are merely transplanted to another part of the mildew field, their infection is a certainty, provided the mildew season lasts and the children remain. How long it may be before efficient infection will occur in their new position is a question of local conditions and of the consequent forwardness or backwardness of the fungus growth. The fungi may not have started when the children arrive, and may not start for one,

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