Consequently when an analyst in England finding " true coli " in 1 cc. con
demns a water, because it shows recent pollution, he is right in a great majority of
the cases, and in the remainder the worst that can be said of his opinion, is, that he has
slightly erred on the side of overcaution, for it must be remembered that the whole
of the 10 organisms comprising his " true coli " are originally of fecal origin. Now
in India things are entirely different A reference to the table shows at once
that the coli communis of Escherich is a very rare organism in the waters of this
country, whereas the other organisms that are included in Houston's definition are
extraordinarily common :—
Quarter
Quarter
Quarter
______.
ending 30th ending 31st ending 31st
September December
March 1
1908.
1908.
1909.
(1) Number of samples examined
...
...
...
7 6
85
78
(2) Number of samples that contain " Coll ",
according to Houston.
63
57
45
(3) Number of samples that contain true bacillus
coli communis of Escherich.
13
13
11
(4) Number of samples in which the only organism
that falls under the definition of Houston's
25
22
22
" Coli " is bacillus Grunthal.
(5) Number of samples containing mixtures of
2 5 2 2
12
Grunthal, acidi lactici, and others of
Houston's " Coli " group.
(6) Number containing no " Coli " of Houston
...
13
28
33
Hence the limit of pollution allowed in England (which even there errs on the
side of over-strictness) if rigidly enforced in this country would condemn unnecessarily.
a great percentage of all samples. In addition to this, considering these facts (1)
that much of the contamination in large schemes in this country is derived from
animals other than man, (2) that true coli communis of Escherich is often very rare
in the fœces of man and other animals, (3) (a fact which will be demonstrated later
on) that the bacteriological flora of the fœces of man and animals varies at different
times of the year, we consider that it is established, beyond all reasonable doubt, that
the conditions as regards water analysis in India are radically different from those in
Europe ; that standards in use in cold climates are useless, and worse than useless,
when applied. to tropical countries ; and also, that the only possible way of ascertaining
the real meaning of the conditions found is to separate the individual species of bacilli
by well-established tests, and to study their characteristics and their position in
nature.
Before closing this section we wish to make it quite clear that the term " coli.
group " is never used in this report in connection with our work, that coli communis
means the true coli communis of Escherich, the organism that gives all the various,
characteristics mentioned in the foregoing paragraphs quoted from different authors,
and in addition to these, that it ferments dulcit, does not ferment saccharose,.
adonit, inulin and does not give the Voges and Proskauer reaction ; when any
different meaning is applied to the term "coli " it will be found in quotation marks.
The names given to the organisms in the water reports are taken from the.
classification used. by MacConkey (vide table III), with this exception, that an organism
that differs from these in motility only, is still named as though this characteristic were
in accordance with the table, but an asterisk is placed after the name.
We may say that we are not by any means satisfied with this method of naming
bacilli, and in future we expect to use numbers for the different species on the lines.
suggested by MacConkey in the table III ; there are, however, some very apparent
advantages in names, if anything like a uniform nomenclature can be arrived. at.