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maintained in 1889, the water delivered, by the Companies
having- been " on the average, of even better quality than that
delivered during the year 1888." But the monthly variation
in the temperature of the water was, as usual, very great (viz.,
from 37°.8 Fahr. in December, to 70°.2 in July = 32°.4), that
of the Kent Company's deep well water being 4°.3 only, viz.,
from 51°.1 in February to 55°.4 in July. Thus this water
remains cool and refreshing in summer, and is less likely to
become frozen in the service pipes in winter; " whilst river
water at 70° or even 65° Fahr., is vapid and unpalatable, and at
39° Fahr. is soon cooled to the freezing point." The river
water is soft by comparison with the deep well water, which
owes its hardness to the much larger proportion of mineral
substances which it contains, and which compose the great bulk
of the "solid matters." The hardness of the water, sufficiently
great to materially diminish its value for washing, steam, and
industrial purposes generally, is almost entirely due to the
presence of bi-carbonate of lime in solution : this bi-carbonate
of lime can be readily removed by treating the water with lime
before delivery, as is so successfully done by the Colne
Valley Company ; whereby the hardness of that Company's
water is reduced to from one-fourth to one-fifth of its original
amount—in 1889 from 29r,9 to 74'0 ; the hardness of the Thames
water being 20'2. This mode of softening is by far the most
economical, for it entails only about one-eightieth of the expense
which devolves upon the private consumer in the shape of
additional soap required for washing purposes. The small
proportion of organic material which the solid matters contain,
is of the greatest importance in connection with the use of the
water for drinking purposes ; as it may be of the most objectionable
character, on account of its origin—such as the drainage
from manured land, the effluents from sewage works, or even
raw sewage itself. The animal matter may at times be accompanied
by zymotic poisons dangerous to health—although the
chances of such substances reaching the consumer are reduced
by filtration, and by the exclusion of flood-waters from the
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