As the whole interest of Dr. Woodward's contribution to the subject centres in his experimental work, it is unnecessary to refer specially to the questions he has raised in respect to the incidence of measles, or to the sources of error he suggests in Dr. Salisbury's observations.

Returning now to Professor Wood's paper, Dr. William Pepper's experiments have next to be considered; and to save time it will be as well to take advantage of the light Dr. Pepper subsequently shed on them. In his joint work with Dr. Meigs, referred to in the first chapter, in the article on Measles, occurs the following:

...

"In 1862 Dr. Salisbury, of Ohio, published two elaborate articles, in which he attributed measles to the action of the fungus developed on damp, mouldy straw. He reported the results of numerous cases in which this fungus had been inoculated, with the production of a modified form of rubeola, which, however, protects the system against a future attack of true measles; and also instances where measles had broken out in camps where damp straw was used for bedding.

"A complete examination of this question, embodying the evidence of Dr. Woodward . . . and the experiments of Dr. C. E. Smith, and one of ourselves, will be found in a paper by Dr. H. C. Wood, jr., in The American Journal of the Medical Sciences, October 1868, p. 342.

"The results of the inoculation of nearly fifty cases prove that, in nearly every instance, the introduction of the straw fungus into the system is entirely without effect; and that in the few cases where any symptoms have followed they have not been those of true rubeola, nor have they protected the system from an attack of genuine measles.

"In regard to the occurrence of camp measles also, Dr. Woodward remarks that it prevailed almost exclusively in regiments raised in the rural districts, while those from cities and towns were more or less completely exempt; and that the inevitable inference from this, confirmed by personal inquiry, is that the recruits from the country had generally escaped the disease before their enlistment, while those from towns had usually

suffered from it at some previous period; a condition of things entirely at variance with the idea that the straw fungus is the veritable cause of measles." [The italics are mine.]

Several grave and inexcusable errors are seen here. A very cursory examination would have sufficed to have shown Dr. Pepper that Dr. Salisbury did not attribute measles to the action of the straw fungus; that he did not report that his inoculations with this fungus produced a modified form of rubeola; that they protected the system against true measles, &c. It is always unfortunate when, through inattention or misconception, a writer not only disregards the words but twists the views of another-especially when, as in this instance, he makes him say precisely what he takes especial pains not to say. It was to little purpose that Dr. Salisbury hedged round his conclusions with a "perhaps," or a "possibility," or with an injunction as to "careful and extended experiments;" for his hedges were all ruthlessly thrown down by those who went to work in the same field, and from whom, therefore, exact knowledge of what their predecessor had done might have been reasonably expected.

Not to waste further time, however, over slovenly errors that have done irreparable mischief, the only question of importance now arising out of the experiments of Dr. Pepper are whether they affect, injuriously, the statements of Dr. Salisbury as to matter of fact, or whether they clash with the results of his inoculations. Dr. Salisbury's statements were to the effect that a certain quantity of certain parts of certain fungi, grown on certain fresh or clean wheaten straw from a certain stack, under certain conditions of heat, moisture, and shade, in a certain locality, at a certain season, when introduced through the skin of the arm into the living bodies of certain persons in a certain manner, had caused certain local and general symptoms of a measly character, lasting a certain time; that similar inoculations made in the same persons within a certain time after the first inoculations, had either failed to induce similar manifestations, or very slight similar manifestations which had passed away in a day or two: and, further, that the inoculations

described appeared, for the reasons given, to render the inoculated insusceptible to ordinary measles. This was about all that Dr. Salisbury "claimed," although he suggested that there was, or left it to be inferred that there might be, not only an affinity between "camp" measles and farmers' measles, and between these and the mild morbilloid exanthem caused by the inoculation of straw fungi, but between all of these affections and ordinary or normal measles.

Do "the results of the inoculations of nearly fifty cases" with the straw fungus affect or invalidate the statements of Dr. Salisbury in regard to his inoculations? Taking Dr. Pepper's latest account we learn "that in the few cases where any symptoms have followed, they have not been those of true rubeola." From this it follows-the inference indeed is forced -that the symptoms in these few cases were those of false or spurious rubeola, or of some kind of rubeola other than true. As Dr. Salisbury did not "claim" to have caused "true rubeola," these few cases, therefore, were similar in kind to his, though they may have differed in degree. Looking at the details of the inoculations made by Dr. Pepper given in Professor Wood's paper, it will be seen that one of the children in the first batch of seven "had some irritation around the point of inoculation, followed in a day or two with symptoms of a common cold in the head which soon passed of." And this was precisely the effect of some of Dr. Salisbury's inoculations. The attempt to explain away this common cold by suggesting that it "might have been an accidental circumstance and not at all owing to the inoculation, as it did not appear in any of the twenty-one other cases," would have had more force if Dr. Pepper had succeeded in introducing a sufficiency of the specific element into the inoculation wound to cause local parasitism in all the other cases. The seventh child, aged ten, " had some irritation around the point of inoculation" followed by the cold. None of the others had any irritation around the point of inoculation or a cold. As therefore the seventh case squares with Dr. Salisbury's cases, and as there was neither a local irritation, nor a common cold in any one of the twenty-one cases, it looks very

much as though the inoculation and the cold were cause and effect. At the same time, of course, the cold may not have been a consequence of the parasitism of the vegetation introduced.

A curious discrepancy, by the way, will be found in relation to this matter in looking at the account of Dr. Pepper's research in Professor Wood's paper, and at the notice of it in the Treatise. In the former Dr. Pepper says: "Thus, out of twenty-two subjects experimented upon, one only had any symptoms developed." In the latter occurs: "In the few cases where any symptoms have followed" (inoculation) "they have not been those of true rubeola." Now as Dr. Woodward explicitly states that the only effect on the organism following his inoculations was the occasional formation of a little ulcer, and as Dr. Pepper's inoculations were barren of results except in the one instance, it is not easy to see where the few cases in which the symptoms were not "those of true rubeola" come in. There is some mystification here, but it may be left.

Indeed further consideration of Dr. Pepper's research is superfluous. For even if we concur with him that the cold might have been an accidental circumstance, and if we strike out the few cases of spurious rubeola that were overlooked or unrecorded in the first instance, we merely bring all his cases on a plane with Dr. Woodward's; and as Dr. Pepper would appear to have had similar views of the nature of the vegetation he inoculated to those of Dr. Woodward, what applies to the one series of inoculation applies to the other.

The experiments referred to in Professor Wood's paper are the only ones, so far as I can learn, that have been undertaken expressly to test Dr. Salisbury's observations. This is the sum of the experimental evidence; and on the strength of it the whole etiological world has stood by contentedly, and in the full assurance that the whole question has been worked out in masterly fashion, and has in fact been finally set at rest. The results obtained by his countrymen were accepted with alacrity out of America as a complete refutation of all that had been advanced by Dr. Salisbury; and the judgment then arrived at has been passed on to the present time by writers who, it would be charitable to suppose, have taken it to be sound on trust.

CHAPTER III.

Dr. Salisbury's inferences-The "straw mildew theory" not his but suggested by his views-Protection by inoculation superfluous—The great importance, botanically, of his experiments with the straw fungi -Hallier's cultivations of the measles contagium-Dr. Salisbury's demonstration of the organic continuity of a pathophyte and a fungus -The parasitic life of the straw fungi in the human host-Inoculation of the contagium vivum of measles-Identity of the phytic forms in the contagium with the straw fungi.

THE testimony which is supposed, or has been supposed, to be sufficient to upset the statements of Dr. Salisbury concerning the effects of the inoculations of straw fungi in himself and others, calls, I submit, for the severest examination. From the internal evidence to be found in his papers, which can be fully appreciated only by those who read them; from the evidence tendered by witnesses under the impression that it put him in the wrong; and from collateral evidence, most of which will be produced; I arrive at the conclusion that all the statements of Dr. Salisbury as to matters of fact are strictly correct in every particular. I see no reason whatever for doubt being thrown on any one of them; and supported as they are by strong circumstantial evidence, it would take a deal of negative experimental evidence of the very highest character to shake them. In short, they may safely be consigned to the future for confirmation.

But Dr. Salisbury's views remain to be considered-his suggestions and inferences or speculations. These have been so mixed up with his facts that we cannot separate them without looking to his own words. The so-called "straw mildew