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observation that the much-desired purification of the river
has occupied much of public attention. It was the generally
prevailing opinion, when the subject was first seriously
examined, that the waters of the Thames, polluted as they
are by the sewage of a population of upwards of three
millions, disengaged from its surface noxious gaseous matter
mixed with the peculiar miasmatic principles, from which
originate the most destructive diseases, and that to such
admixture with the atmosphere the supposed prevalence of
epidemic disease on its banks was due. I say supposed,
because it has been questioned whether disease be more
prevalent at or near the shores of the river, than in remoter
places, other circumstances being equal.
Within the last twelvemonths a change has taken place
in the state of opinion of scientific men, —a change more
apparent, however, than real. At first the mischief-producing
power was freely imputed to the river; now, it is not
the river which is in fault, but the mud, which, being left
bare and exposed for some hours during the tidal period,
causes, in hot weather particularly, an offensive stench. All
the change that I can understand is, that, instead of attributing
the mischief to the whole, the particular offending
part has been discovered. My own opinion is, that the
water of the river is not exonerated,—that it contains in suspension
that which forms, when deposited, the offensive mud;
and that the suspended matter is washed into the river from
the sewers principally, but besides that, from the extensive
use of the river as a receiver of filth from the almost
numberless vessels navigating it.
This very moderate correction of opinion, being a
refinement rather than a correction, is likely to have material
influence over our expenditure. Two distinct objects have