304 



SCIENCE 



[Vol. IV., No. 86. 



susceptible animals; and that such virus lost nothing 

 in virulence by being grown in such a medium. 1 I 

 will not trouble you with the theory of immunity 

 which I developed from these experiments. Like 

 other American work, it may have no value; but it 

 may interest you to know that an able German writer 

 in the last number of Virchow's Archiv has pro- 

 pounded a theory, which, in its most important points, 

 is identical with my own. 



In 1880 Mr. Chauveau published some observations 

 and experiments which indicated that even a very 

 virulent virus of a fatal disease might be made to 

 produce a mild attack, if the dose administered was 

 sufficiently small. About the same time I demon- 

 strated by more numerous and direct experiments 

 that this was true; but I went beyond this, and have 

 the incontestible priority of demonstrating, — 



1. That a certain number of the most virulent and 

 fatal germs may be introduced into the most suscep- 

 tible body without producing the least appreciable 

 effect; 2 



2. That by increasing this number slightly, but still 

 using a relatively small dose, germs which ordinarily 

 multiplied throughout the whole body, and produced 

 a constitutional disease, may be compelled to multiply 

 locally, and cause only an insignificant local lesion 

 without constitutional symptoms; 3 



3. That this local multiplication confers an im- 

 munity upon the whole body ; 4 



4. That the immunity produced by a single inocu- 

 lation with this diluted virus equals that produced by 

 two inoculations with Pasteur's attenuated virus. 5 



Again : when Pasteur announced his discovery of 

 the method of attenuating the virus of fowl-cholera, 

 he coupled it with the theory that this attenuation 

 was due to the action of atmospheric oxygen; and, 

 although the evidence in favor of this theory was 

 neither direct nor abundant, what there was of it came 

 direct from Paris, and this was sufficient to secure 

 it universal attention and unqualified indorsement 

 at the hands of scientific editors. A few experiments 

 led me to conclude, however, that this theory was 

 incorrect, that the attenuation could be secured in 

 the absence of oxygen as well as in its presence, and 

 that it was really due to loss of vitality, the result of 

 keeping the germs for a considerable time under un- 

 favorable conditions of life. 6 



It is true that these conclusions did not receive 

 the least notice, favorable or unfavorable, either at 

 home or abroad; but, as they have since been estab- 

 lished beyond question by the elaborate researches of 

 Chauveau and others, I am inclined to think that 

 the fault was neither with me nor my experiments, 

 but that it is confined to the fact of the work being 

 done by an American, and on American soil. 



I need no more than call your attention here to 

 the fact that I demonstrated which one of the several 

 germs that had been described as peculiar to swine- 

 plague was the actual cause of the disease, and that 

 this was more than a year before the same experi- 

 ments were duplicated by Pasteur and his assistants, 

 who, nevertheless, succeeded in bearing off the honors 

 that belonged to the American discoverer. This 

 subject was pi need before your readers in sufficient 

 detail in a recent number of Science. 1 



In regard to the peculiarities of the germ of fowl- 



1 Department of agriculture, Annual report, 1881 and 1882, 

 pp. 283-300. 



2 Department of agriculture, Annual report, 1883, p. 48. 



3 Ibid., 1881 and 1882, pp. 285-288; also 1883, pp. 44-49. 



4 Ibid., 1881 and 1882, p. 288. 

 e Ibid., 1881 and 18S2, p. 288. 



e Ibid.', 1881 and 1882', pp. 283, 284. 

 7 Science, iii. p. 155. 



cholera, and the exact effect of- disinfectants and vari- 

 ous conditions of existence upon it, you will find in 

 my reports the record of nearly one hundred apd 

 fifty experiments which it has seemed to me might 

 have a little, though possibly a very slight, value from 

 the light which they throw upon the germ-theory in 

 general, and especially upon that group of diseases 

 caused by organisms which do not form spores. 1 



The admirers of Koch are ever on the alert for an 

 opportunity to enlarge upon the perfection of his 

 apparatus and the security of his processes. They 

 forget, however, that the most satisfactory work 

 which he ever did, that which raised him from an 

 obscure physician to be an acknowledged scientific 

 authority, was accomplished with an apparatus so 

 primitive and imperfect, that, were any one to use it 

 to-day, it would only create ridicule and contempt. 

 I refer to his cultivations of the bacillus anthracis in 

 unsterilized liquid on ordinary microscopic slides, 

 placed over wet sand in a soup-plate to prevent evap- 

 oration, covered with a plate of glass, and warmed 

 over an oil-lamp. His disciples can, perhaps, afford 

 to criticise imperfect apparatus now; but it may not 

 be out of place to remind them, that, if their master's 

 first work had been rejected on this account, he 

 would probably still be an unknown physician in an 

 obscure German hamlet. 



After all, what is there in Koch's method of culti- 

 vation on the surface of solid media that makes it 

 preferable, or even equal, for general purposes, to 

 cultivation in liquids ? Is any scientific man at this 

 day so ignorant as to believe that the intermittent 

 heating of blood-serum for half a dozen times to 137° 

 F. (58° C.) is sufficient to safely sterilize it? 2 Is it 

 not an incontestible fact that cultivations on solid 

 substances cannot be made, examined, and repro- 

 duced, without exposing a large surface to contact 

 with unsterilized air and the countless germs which 

 it contains ? 



It is not my desire, however, to detract in any way 

 from the well-earned reputation of Dr. Koch and Mr. 

 Pasteur (there is no danger that they will ever re- 

 ceive too much honor) ; but, when American science 

 is sneered at and rejected because of alleged imper- 

 fections, one can scarcely avoid calling attention to 

 the fact that Europeans also are fallible, and their 

 methods not beyond criticism. 



You do not seem to be aware, Mr. Editor, of the 

 fact that appropriations for the investigation of 

 the contagious diseases of animals have been made 

 on a liberal scale for the past six years, and that a 

 considerable part of this money has been used in the 

 study of micro-organisms. The results of these in- 

 vestigations have been so satisfactory to the people 

 at large and to congress, that a permanent bureau 

 was established at the last session, a part of the 

 duties of which is to continue this line of research. 

 I have had a laboratory and an experiment-station 

 under my direction in Washington for more than a 

 year. And while I am willing to admit fallibility 

 and imperfections, if one can judge from scientific 

 articles and from the reports of those who have vis- 

 ited the laboratories of Koch and Pasteur, I see no 

 reason why we should fear a comparison of our labo- 

 ratory, apparatus, and methods, with those in use on 

 the other side of the water. 



It is true that the enormous development of our 

 animal industries brings up a multitude of inquiries 

 foreign to the subject of micro-organisms, which 



1 Department of agriculture, Annual report, 1880. Ibid., 1881 

 and 1882, pp. 272-306. Ibid., 1883, pp. 44-52. 



2 Les organismesvivantes de l'atmosphere (P. Miquel, Paris, 

 1883), footnote, pp. 154, 155. Department of agriculture, Annual 

 report, 1881 and 1882, p. 264. 



