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of microbes removed is 98.24: the maximum being 100.00,
and the minimum 95.25 per cent. This company, it is stated,
except in the month of August, delivered water of " a very
high degree of bacterial purity ; rivalling, in many cases, deepwell
water in this respect. In the month of February, indeed,
when the Thames at the intake contained 13,947 microbes,
or their spores, per c.c., this company's water, which was
being pumped from the general filter well into the supply
mains, was absolutely sterile."The" average number of
microbes in 1 c.c. of the company's water during the year,
omitting an abnormal sample in August, was 18. The West
Middlesex Company has storage for 6.7 days : the average
thickness of sand on the filter is 2.6 feet, the rate of filtration
being about l⅓ gallons per square foot per hour. The average
percentage of microbes removed was 98.87 ; the maximum
being 99.94, the minimum 92.67 per cent. The average
number of microbes per c.c. during the year, omitting an
abnormal sample in August, was 15 only, " an excellent
record." The lowest number was 5 per c.c., in December,
" whilst the raw water at the intake contained at the same time
6,316 microbes per c.c. The Grand Junction Company have
storage for 3½ days only; .the average thickness of sand on
the filter is 1¾ feet, the average rate of filtration, per square
foot per hour, being 2.2 gallons. The average percentage of
microbes removed was 97.12, the maximum being 99.77, the
minimum 85.95 per cent. Four of the samples collected from
the general well at this Company's works at Kew—in
January, June, August and December—"contained an excess
of microbes over 100 per cent. ; and samples collected at
Hampton, in February, June, and December, also contained
an abnormal number of microbes." One filter at the Kew
Bridge Works "never furnished an abnormal sample throughout
the year" (but six samples only were examined), whilst
another filter which had " undergone a thorough " (and prolonged)
" washing of all the materials of which it was composed,
so as to become practically a new filter, yielded, the