hypothesis as to the existence of a virus in solution, and that is that such a substance, which was present in our experiment in nonfatal amounts, should be continuously furnished by the vibrio itself, during its growth in the body of the living animal.  But it is of little importance since the hypothesis supposes the forming and necessary existence of the vibrio. [Footnote:  The regular limits, oblige me to omit a portion of my speech.]

I hasten to touch upon another series of observations which are even more deserving the attention of the surgeon than the preceding:  I desire to speak of the effects of our microbe of pus when associated with the septic vibrio.  There is nothing more easy to superpose—­as it were—­two distinct diseases and to produce what might be called a septicemic purulent infection, or a purulent septicemia.  Whilst the microbe-producing pus, when acting alone, gives rise to a thick pus, white, or sometimes with a yellow or bluish tint, not putrid, diffused or enclosed by the so-called pyogenic membrane, not dangerous, especially if localized in cellular tissue, ready, if the expression may be used for rapid resorption; on the other hand the smallest abscess produced by this organism when associated with the septic vibrio takes on a thick gangrenous appearance, putrid, greenish and infiltrating the softened tissues.  In this case the microbe of pus carried so to speak by the septic vibrio, accompanies it throughout the body:  the highly-inflamed muscular tissues, full of serous fluid, showing also globules of pus here and there, are like a kneading of the two organisms.

By a similar procedure the effects of the anthrax bacteridium and the microbe of pus may be combined and the two diseases may be superposed, so as to obtain a purulent anthrax or an anthracoid purulent infection.  Care must be taken not to exaggerate the predominance of the new microbe over the bacteridum.  If the microbe be associated with the latter in sufficient amount it may crowd it out completely—­prevent it from growing in the body at all.  Anthrax does not appear, and the infection, entirely local, becomes merely an abscess whose cure is easy.  The microbe-producing pus and the septic vibrio (not) [Footnote:  There is undoubtedly a mistake in the original.  Pasteur could not have meant to say that both bacteria are anaerobes.  The word “not” is introduced to correct the error.—­Translator.] being both anaerobes, as we have demonstrated, it is evident that the latter will not much disturb its neighbor.  Nutrient substances, fluid or solid, can scarcely be deficient in the tissues from such minute organisms.  But the anthrax bacteridium is exclusively aerobic, and the proportion of oxygen is far from being equally distributed throughout the tissues:  innumerable conditions can diminish or exhaust the supply here and there, and since the microbe-producing pus is also aerobic, it can be understood how, by using a quantity slightly greater than that of the bacteridium it might easily deprive the latter of the oxygen necessary for it.  But the explanation of the fact is of little importance:  it is certain that under some conditions the microbe we are speaking of entirely prevents the development of the bacteridium.