| “In 1868, | 1,000 | In 1870, | 795 | In 1872, | 1,243 |
| In 1869, | 1,016 | In 1871, | 928 | In 1873, | 917 |
“7th. That there is no hope of this disgusting state of the river being so far remedied as to preclude the presence of animal and other offensive matters, even in the filtered Thames water as delivered in the metropolis.
“8th. That the Thames should, therefore, as early as possible, be abandoned as a source of water for domestic use.
“9th. That the temperature of the water drawn from the company’s mains is liable to excessive fluctuations, being near the freezing point in winter and so warm in summer as to be vapid and unpalatable.”
The Lea River is also condemned as a source of water supply.
Prof. Chandler, of New York, quotes the authority of eminent scientists, who say the Thames, a short distance above London, is wholesome, palatable, and agreeable, and safe for domestic use, notwithstanding the large amount of sewage (the number of grains per gallon being three times that of the Schuylkill), although controlled by strict governmental laws.
QUALITY OF POLLUTION.
Scientists tell us that it is not so much the quantity as the quality of the sewage:
“It is true a large amount of refuse material is of such character as to be, except in excessive quantities, of no appreciable influence on the human system; the addition of the inorganic compounds of lime, soda, potash, etc., would have no deleterious effect; in fact, although the lime compounds increase the hardness of water, and make it less desirable for washing, the presence of a moderate amount of mineral substance makes the water more palatable and very probably more wholesome.
“Then, in case of many waste liquors, which appear to be very offensive, the matter which really could be regarded as injurious is comparatively small in amount. If we consider the character of the substances discharged by different manufacturing establishments, we shall find them very different. Some of them are such as to be universally regarded as unfit to admit to any stream; those, for instance, containing lead, arsenic, etc.; others, such as salts of iron, are scarcely regarded as injurious; thus, the discharge of sulphate of iron (copperas) into a stream already polluted with sewage matter, might, within certain limits, be of positive advantage. Again, in the case of some of the vegetable dye-stuffs, the weak-spent dye liquors, although they communicate a very foul appearance to the water for some distance, yet contain a comparatively small amount of solid matter, and, if discharged into a stream of considerable size, as soon as disseminated through it, are diluted to a very great extent.