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which formerly held a prominent position in this respect, has lost ground to a considerable extent, and
unless measures of a similar nature are adopted, this company, within the next few years, will find
itself surpassed as regards the provision of storage reservoirs by all the other companies deriving their
supplies from the Thames and the Lee. It is, in fact, necessary that the storage reservoirs should be
capable of containing a quantity of water equal to 20 days' average supply, instead of 10 days, as at
present."
Concerning the opportunity which exists for ascertaining the efficiency of each filter, he points
out " It is desirable that the water issued from each filter should be delivered into a distinct well,
so that distinctive examples may be obtained for examination, and failure in the efficiency of filtration
may be traced to the particular filter which is at fault. In the cases of the Chelsea and West
Middlesex Companies the filtered water collects in a general receptacle or well and no means exist of
determining the character of the filtration of each filter bed."
Sir Edward Frankland's report on the results of his monthly bacterioscopic examination of the
water supplied by the several companies contains the following statements—
Chelsea Company.—" Except in June this company delivered water of uniformly excellent
quality, rivalling, in many cases, deep-well water in this respect."
West Middlesex Company.—" Excepting in June and December, this company delivered water
of most excellent bacterial quality, [not infrequently rivalling or excelling in this respect the deep
well water of the Kent Company. The infraction of the standard (100 microbes per c.c.) in December
was only slight (120), but that in June was more serious."
Southwarh and Vauxhall.—" The filtration plants of the Chelsea and West Middlesex Companies
deliver the filtered water into general receptacles or wells, from which the samples for bacterioscopic
examination were drawn, and there was consequently no opportunity at these works for obtaining
separate samples from each of the filter beds. At the South wark Company's works, however, I have
been able to obtain samples from several separate filters, and the above table, giving the results of the
examination of these samples, shows several cases in which effective bacterial filtration was not
attained. Thus, No. 3 filter was not working satisfactorily in July, Nos. 4 and 5 filters were uniformly
and highly satisfactory on every cccasion when samples were drawn from them, the water issuing from
No. 4, on September 9th, being absolutely sterile; but filter No. 8 yielded on four out of ten occasions
unsatisfactory results. Although No. 8 filter leaves much to be desired, the company's record is, on
the whole, greatly superior to that of 1895."
Grand Junction Company.—"The small amount of storage possessed by this company renders it
difficult at all times to maintain efficient bacterial filtration, and six out of the 12 samples collected at
the Hampton works during the year contained an excess of microbes, or their spores, over 100 per c.c.;
whilst five out of the 22 samples collected at the Kew works also contained an abnormal number. As
was the case with nearly all the other companies, the most serious infractions of the standard occurred
in June."
Lambeth Company.—"Excepting in June and December, this company delivered water of
excellent bacterial quality, the infraction of the standard in June being the only serious one, but even
in this month of abnormal results, the number of microbes was much less than that found in the water
of three of the other Thames companies. Altogether, the record of this company is very good, and is
free from violent fluctuations. In December, for instance, when the Thames contained the enormous
number of 160,000 microbes per c.c., and the stored water supplying the filters as many as 56,000, the
number was reduced to 116 per c.c."
New Rixer Company.—" This table shows that out of 31 samples colbcted during the year only
three transgressed the standard of 100 microbes per c.c , whilst one was absolutely sterile. Two out of
the three transgressions occurred in November and December, when extensive repairs were being made
in the filtered water culverts. The samples collected on six occasions from the general filter-well
compare favourably, in respect of bacterial purity, with the deep-well water of the Kent Company."
East London Company.—" From this table it is S3en that out of 31 samples nine contained a
number of microbes in excess of the standard; three of these were taken from three different filterwells
in the month of June, when the filtration plants of nearly every metropolitan water company, for
some unexplained reason, were simultaneously unable to perform efficiently their work of bacterial
purification. Up to the present time I have endeavoured in vain to find an explanation of this singular
phenomenon. If it had occurred only in one or two cases it might have been attributed to accident or
carelessness ; but its general occurrence proves that the cause must be some condition or conditions
affecting both metropolitan rivers. Of the five companies drawing from the Thames, all except the
South wark were smitten with this microbial epidemic in June, and even the Southwark had got it on
the 2nd of the following month. Of the two companies drawing from the Lee, the New River alone
escaped, owing no doubt, to the exceptional sources from which it derives its raw water. The East
London Company had it rather severely, every one of its filter-wells yielding in June water containing
an excess of microbes."
The report of Sir Edward Frankland also includes the following paragraph—
In nature, even the purest waters contain, almost invariably, minute quantities of organic matter;
but in river water the presence of even a small proportion is considered objectionable, partly on
sentimental and partly on hygienic grounds, by reason of the possible origin of some portions of this
organic matter. The water both of the Thames and Lee receives, above the points where it is abstracted
for the purpose of the metropolitan supply, various contributions of organic matter of animal origin, such
as the drainage from manured land, and the effluents of sewage works. This animal matter, though
innocuous in itself, may at any time be accompanied by zymotic matters dangerous to health. But,
although the sentimental objection to the presence of animal matter cannot be removed, it is gratifying
to find, as the result of recent researches, that the zymotic matters of the pathogenic kind are rapidly
destroyed in running water, so that the most minute microscopic inspection of the water as it reaches the
intakes of the various companies has hitherto failed to discover in it a single pathogenic germ. Further,
it is now an established fact that efficient sand filtration would prevent the passage of such germs into