DECEMBER 31, 1806} 
Ned! INO aad 
213 
air ; the vicious circle is at once established. It is difficult to 
say what number of Profews bacilli in an otherwise sound 
article of food would signify danger, and the value of such 
statement depends on the experience of the observer and on 
the circumstances of the case. But as far as mere qualitative 
evidence goes, viewed from the bacteriological standpoint, we 
all live amongst particles of decomposing matter. Should we 
get almost pure cultures of Profews or B. co/d and these forms 
present in large numbers, matters are easy enough—such food 
must be condemned. 
Let us now turn to the Bacter7zz col. Water has been con- 
demned because it contained this organism in small or large 
numbers, and the writer quoted above asserted that ‘‘the colon 
bacillus, if found in potable water, is usually taken as diagnostic 
of sewage contamination,” and ‘‘ its frequent presence in milk 
he derives from the soiled cow and its surroundings, and he 
regards it as par excellence diagnostic of fecal contamination.” 
Many writers believe that water which contains this microbe at 
all, in however small numbers, has in all probability been pol- 
luted with excremental matter, and they regard this bacillus by 
itself as typical and specific of feecal matter. 
Now I consider that the A. co/z, in its various forms, is a rather 
abused organism. With Mr. Stephens I have worked at this 
organism since the beginning of 1894, and have separated it 
wherever I came across it. It is our experience that it occurs in 
some form or another almost anywhere and everywhere : in the 
air, in the soil, in the water, in dust, of course in varying and vari- 
able quantities. We have found it in the secretions of the body 
where direct intestinal contamination could be excluded. It 
occurs in normal saliva, in expectoration, whether of health or 
disease, not occasionally, but practically always. In diphtheritic 
membranes, in abscesses, in theiskin—everywhere it is. Fluids 
and solids exposed to air contain it ; nothing can avoid it. On 
the surface of meat, even frozen mutton, on bread, fruit— 
everywhere it may be found. A few hours after birth it has 
been found in the intestinal tract of infants. We, therefore, 
have come to the conclusion that the 4. cod’ is present in the 
intestines, because it is ubiquitous. outside the animal body, and 
not that its presence anywhere and in any number outside the 
digestive tract necessarily signifies direct filth contamination. 
No doubt animal excreta assist in. keeping up its supply, but 
it seems to me that simply because this bacterium occurs 
somewhere or other, to speak of direct filth contamination 
without other existing evidence is not quite logical. Of 
course it may be said that since filth forms a great source 
of this bacterium, and since the alimentary tracts, soto 
speak, envelops the earth, that therefore the presence of the 
£. colé commune does prove such contamination ; but then 
it comes to this, that from a bacteriological standpoint we 
live and breathe in decomposing matter.. I, therefore doubt 
whether we have any right to condemn apparently sound water 
or food which contains the 4. co/é comune on the assumption 
that it has been soiled unless we have real or. circumstantial 
evidence of such soiling. If water contains a large number of 
B. colt commune, we may have to condemn it on the score of 
being insufficiently filtered if the source of such drinking-water 
contains the B. colé commune: but in the absence of other 
evidence we cannot always do that. The bacillus fluorescence 
is almost constantly found wherever the 4. co/z occurs, yet no 
one would regard its presence in water, even in large numbers, 
as absolute evidence of direct filth contamination Yet the 
above observer concluded that the presence of the~ bacillus 
fluorescence in milk may be taken as presumptive evidence ‘of 
added water: this is a veductio ad absurduim. Time forbids to 
say any more about the #4. co/z comune, and I am not here to 
discuss it. ? . . 
I know of few organisms which are so indifferent with regard 
to the medium on or in which’ they are grown; aerobiosis or 
anaerobiosis, high or low temperatures, acid or alkaline reactions, 
light or darkness do not affect the Bacteria coli group to any 
marked degree. Atthe same time they are chemically extremely 
active organisms, and therefore their normal presence in the 
alimentary tract can’ hardly be of physiological indifference to 
us and animals. I incline to the belief that their influence in 
disease is secondary rather than primary, but I shall not discuss 
this point here. 
Now, when we are dealing with organisms which are capable 
of growing and acting on dead as well as on living tissues, 
which are furthermore capable of great and varied chemical 
activity, and also resist external influences extremely well, and 
NO. 1418, VOL. 55 | 
readily vary under such influences, it seems to me that an im- 
portant point may be raised. If there be anything in adapta- 
tion, then I think the animal body must have adapted itselfas much 
to the Bacteria coli group, as the latter, no doubt, has adapted 
itself to the animal body. The two organisms, viz. the Bacterdunz 
cofé and the animal body must be well balanced ; if the balance is 
disturbed, one of them must go down. Symbiosis, whether obli- 
gatory or facultative, is a problem which has hardly been touched 
upon as existing between man and low forms of germs. We know 
that plants make use of micro-organisms, and that vegetation is 
immensely assisted by nitrifying organisms. Under absolutely 
sterile conditions of growtha plant thrives badly. Experiments 
and observations are needed to show how animals would thrive 
on sterile food and in sterile surroundings. Pasteur, in 1885, 
expressed the opinion that they would do badly under such condi- 
tions. Nuttalland Thierfelder have shown that a guinea-pig brought 
aseptically into this world may be kept in good condition under 
sterile surroundings for 8 to 14 days, and from their experiments 
they argue that the presence of bacteria in the intestinal tract 
is not necessary to life. The obvious criticism is that a week 
or two for such experiments is too short a period, and that 
it would require observations carried on for months before it 
could be definitely stated whether or no bacteria are necessary 
not for life but for perfect development. 
Fermi seems to incline towards a belief in a form of sym- 
biosis existing between the 4. co/z group and the intestinal 
mucosa. There are observations which tend to show that lower 
forms of animal life do not grow or thrive well on sterile food. 
It seems possible from studying Neumeister’s work on physio- 
logical chemistry, that some forms of bacteria—not necessarily 
the &. cold commune—are of use in assisting fermentative pro- 
cesses, and in aiding in the resorption and absorption of pro- 
ducts of digestion, and it is certain that as putrefactive organisms 
they do good. Nor is it impossible that they are capable of 
splitting up certain toxic substances, thus rendering them harm- 
less. The question of adaptation of the body to bacteria is well 
worthy of extended study; but while it is still a matter of 
speculation, it is safer to dismiss it with this brief allusion. 
Taking a summary review of the points mentioned, we have 
seen that under ordinary conditions sound food often contains 
large quantities of bacteria, so that we habitually consume num- 
berless micro-organisms. Further, the qualitative examination 
shows that we are habitually consuming such forms as the B. co/z 
commune and Proteus. It is well that we should know the flora 
of apparently good food, and become familiarised with the idea, 
alarming to many, no doubt, that many articles of food daily 
consumed contain bacteria, some of which are described by 
bacteriologists as the typical organisms of the intestinal contents 
and of decomposing matter. 
Ido not wish to be misunderstood. I am not advocating the 
view that good food should be particularly rich in bacteria. “All 
possible chance of direct foecal, sewage, or other contamination 
should be, and must be, carefully avoided. On the other hand, we 
must not introduce a fictitious standard, and simply put on one 
side physiological facts and common-sense experience. Simi- 
larly we must pause before we give certain bacteria an absolutely 
specific significance which they possibly do not deserve. 
The A. colé conimune by itself does not prove sewage or faecal 
pollution ; it may and often does point to it, under certain condi- 
tions which Dr. Klein has recently defined, but it cannot un- 
conditionally prove it. Again, its importance as the cause of 
enteritis inust not be exaggerated. Thousands of co/z bacilliare 
periodically taken in with the food, and they pass into an 
alimentary canal already full of these bacilli. This is a point 
worthy of consideration. True in an enteritis the 4. co/z may 
be found in pure culture in the dejecta, possessed of virulent 
properties when tested on the animal.’ This merely proves one 
of two things: if the Bacter‘zm coli is the cause of the lesion 
then for some reason or another it must have been transformed 
from a harmlesssaprophyte into an irritant pathogenic organism ; 
but it has not yet been shown that this organism is the cause of 
such a lesion, and therefore its abundant presence in such a 
lesion may be merely a concomitant phenomenon. The exact 
position of this extraordinary organism, or rather group of 
organisms, has not yet been exactly defined. | Many observers 
may not agree with me; my own opinions are, however, based 
upon my personal acquaintance with the Bacterdum cod and its 
varieties. It is of value in water or food examination, not 
because it is absolutely specific of bad or polluted food, but 
because it is easily recognised, and therefore its source can often 
