3IO 



NATURE 



[Aug. lo, 1876 



depends upon the same issue, is the truth or falsity of an 

 exclusive germ-theory in explanation of the origin and 

 spread of the communicable diseases. If the germ-theory 

 of fertilisation can be proved to be untrue, and if living 

 ferments can be proved to originate spontaneously, we 

 should soon cease to hear much about an exclusive germ- 

 theory of disease. This derivative doctrine would not 

 long survive the death of its parents. 



Thus M. Pasteur's theory of fermentation, the popular 

 doctrine omne vivum ex vivo, and the germ-theory of 

 disease, must all be simultaneously overthrown if it can- 

 not be proved by M. Pasteur, or some of his followers, 

 that Bacteria germs are not killed when they are im- 

 mersed in strong liquor potassze raised to 212° F. (100" C). 

 How matters have been brought to this desperate predi- 

 cament may be explained in a very few words. 



Since the year 1862, M. Pasteur has defended four main 

 positions, on the strength of which he has based his 

 germ-theory of fermentation, his repudiation of " spon- 

 taneous generation," and his support to the germ-theory 

 of disease. In the year 1870 and subsequently, I have 

 many times submitted these four positions to an inde- 

 pendent criticism by means of experiment, and the result 

 has been a confirmation of two of them, and a rejection 

 of the remaining two — the rejection being necessitated 

 rather on account of facts obtained by new methods than 

 from any implied defect in the particular range of expe- 

 riments from which so distinguished an investigator as 

 M. Pasteur deduced his opinions. Our respective views 

 on these four points may be thus tabulated : — 



Pasteur Bastian 



1. That all boiled organic I. That some boiled organic 

 infusions havingan acid reaction infusions having an acid reac- 

 will, when protected from con- tion will, when protected from 

 tamination, invariably remain contamination, ferment and 

 pure. swarm with Bacteria. 



2. That all Bacteria and their 2. Do. 

 germs are killed in such boiled 



acid fluids. 



3. That sotne boiled organic 3. Do. 

 infusions having a neutral, or 



slightly alkaline reaction, will 

 not remain pure even when 

 protected from contamination. 

 They will, on the contrary, 

 ferment and swarm with Bac- 

 teria. 



4. That all Bacteria and their 4. That all Bacteria and their 

 germs are not killed in such germs are killed in such neu- 

 neutral or slightly alkaline tral or slightly alkaline fluids 

 fluids raised to 212° F. (100° raised to 212° F. (100° C). 

 C). 



Omitting, for the present, all intermediate stages of the 

 controversy which has now been carried on for several 

 years between one or other of M. Pasteur's followers and 

 myself, I will proceed to show how the questions between 

 us have been affected by my latest researches. 



The results obtained in these researches have been 

 embodied in a memoir communicated to the Royal 

 Society on June 15, of which an abstract was published 

 in Nature, vol. xiii., p. 220. Avery short "Note" on 

 the subject of these researches was also submitted to the 

 Acadimie des Sciences on July 10, and subsequently pub- 

 lished in the number of the Cotnptes Reiidus bearing that 

 date. M. Pasteur replied to this note at the next meeting 

 of the Academy {Cojnptes Rendus, July 17), at a time 

 when he would appear not to have seen the fuller abstract 

 of my researches published in Nature. This will ac- 

 count for an error into which he seems to have fallen in 

 regard to one of the most important conditions prescribed 

 for some of my experiments, to which I shall have occa- 

 sion presently to refer. In the first place, however, I 

 must call attention to a different part of the subject. 



One of the most notable results of my recent work is 

 this : — I have ascertained that a moderately acid urine 



will, after it has been boiled, remain pure when kept free 

 from contamination at a temperature of 77°-86° F. (25°- 

 30° C), though the same specimen of " sterilised " urine 

 will ferment and swarm with Bacteria in less than three 

 days, if it is maintained at the higher temperature of 

 122° F. (50° C). Many acid vegetal infusions will behave 

 in precisely the same manner. 



Here, then, is a ready means by which any careful 

 experimenter may ascertain whether M. Pasteur is not 

 wrong in maintaining his proposition No. i. And if this 

 is the case, then there is nothing for M. Pasteur to do 

 but to renounce his exclusive germ-theory of fermenta- 

 tion, and to adopt the doctrine of "spontaneous genera- 

 tion," since he still declares that Bacteria and their germs 

 are killed in acid fluids raised to 212° F. (100° C). His 

 words are {Coinptes Rendjts, July 17, p. 179) : — "J'ai 

 prouvd directement qu'ils perissent dans un milieu acide 

 h. 100 degrcs." 



But there is another means ot establishing the truth of 

 my conclusions derived from these recent researches to 

 which I will now allude. This is the point principally 

 referred to in my " Note " to the Academy, and upon 

 which M. Pasteur dwells in the above-mentioned com- 

 munication. 



As regards the frequent fertility of boiled organic fluids 

 having a neutral or faintly alkaline reaction (No. 3) it 

 will be seen that M. Pasteur and myself are thoroughly 

 agreed, notwithstanding Prof Tyndall's representations to 

 the contrary, made in the columns of this journal in the 

 early part of this year. M. Pasteur now says {Comptes 

 Rendus, July 17, p. 178) : — "Je m'empresse de declarer que 

 les expdriences de M. le Dr. Bastian sont, en effet, tres 

 exactes ; elles donnent Ic plus souvent les rdsultats qu'il 

 indique ... II n'y a donc^entre M. Bastian et moi 

 qu'une difference dans I'interprdtation d'expdriences qui 

 nous sont maintenant communes." The difference of 

 interpretation to which M. Pasteur alludes depends upon 

 our difference of view in regard to position No. 4. It 

 was specially with the hope of dissipating any doubt 

 remaining upon this part of the question that one section 

 of my new experiments was undertaken. I determined 

 to submit M. Pasteur's interpretation to the test of direct 

 experiments, conducted in a way likely to yield decisive 

 results. 



If the fertility of the boiled neutralised fluids or infu- 

 sions were really due to the survival of germs, as M. 

 Pasteur supposes, then the boiling of the fluid in its acid 

 state (when its germs would by admission be destroyed), 

 and the subsequent addition to it of a sufficient amount of 

 boiled liquor potassse, without extraneous contamination, 

 should be attended by negative results — that is, the fluid 

 should remain pure, according to M. Pasteur, if it were 

 really germless. 



But numerous experiments performed in this manner 

 have shown me that sterilised urine, to which boiled 

 liquor potassse, in proper quantity, is added, will ferment 

 and swarm with Bacteria in a few days — and all the more 

 quickly if the experimental vessels and their fluids are 

 maintained at a temperature of 122° F. (50° C). 



M. Pasteur, whilst admitting che facts, says that this 

 addition of boiled liquor potassae to sterilised urine causes 

 the mixture to ferment because such added liquor potassEe 

 contains germs which were not killed when this fluid was 

 raised to 212° F. (100° C). 



This, truly, is an astounding hypothesis. My reply, 

 however, is simple. It was an objection already antici- 

 pated and met by me, as any one may see by referring to 

 the concluding portion of my abstract, as published in 

 Nature. 



The answer is this : — If boiled liquor potassa; were a 

 germ- containing medium, then one or two drops of it (as 

 of other germ-containing media) would always be capable 

 of contaminating many ounces, or even a gallon or more 

 of sterilised acid urine. This, however, is never the case. 



