The case I have been describing, and which I am still keeping under observation, demonstrates once more the uselessness of the human large intestine; it should convert the most sceptical critic. But it also shows that the suppression of nearly the entire large intestine for several years does not completely get rid of the intestinal flora. Even without this evidence, however, I do not suggest that removal of the large intestine can be thought of as a means to prevent the pernicious effect of the intestinal flora.
Is it possible, without operative interference, to take direct action against the intestinal flora by the use of antiseptics? Consideration of this is already ancient history. When the theory that the intestine was a source of auto-intoxication was propounded, M. Bouchard[122] made the attempt to cure such cases by disinfecting the digestive tube with [Greek: b]-naphthol. He found, however, that that antiseptic, like many others, not only did not completely disinfect the intestine but sometimes had a harmful effect on the body.
M. Stern[123] has shown, in an elaborate memoir, that such antiseptics as calomel, salol, [Greek: b]-naphthol, naphthaline, and camphor, when administered in quantities compatible with health, do not disinfect the digestive tube at all. More recently M. Strasburger[124] has shown that when naphthaline has been given in quantities sufficient to impart its odour to the fæces, the intestinal microbes, so far from being diminished, are even increased in numbers. On the other hand, after meals consisting of milk to which there has been added an antiseptic in the proportion of a quarter of a gram to the litre, the intestinal microbes are really reduced in number. Strasburger obtained his best results with tanocol. Two persons who used, according to this method, three to six grams of tanacol per day, displayed a notable reduction in quantity of the intestinal flora.
Strasburger’s conclusion was that “the attempt to destroy the intestinal microbes by the use of chemical agents has little chance of success.” It cannot be denied that under special circumstances it is possible to decrease the number of microbes, especially in the small intestine. But this result is small and may be followed by the contrary effect, for the natural means of defence of the intestine against microbes are weakened, and the intestine itself may be harmed more than the microbes.