Hints and suggestions on school architecture and hygiene : with plans and illustrations for the use of school trustees in Ontario / by J. George Hodgins.

  • Hodgins, J. George (John George), 1821-1912.
Date:
1886
Catalogue details

Licence: Public Domain Mark

Credit: Hints and suggestions on school architecture and hygiene : with plans and illustrations for the use of school trustees in Ontario / by J. George Hodgins. Source: Wellcome Collection.

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    Impure Substances Held in Solution by Water. 29. As to the power of water to hold injurious substances in solution, I quote the following striking passage on the subject from a lecture by Dr. Bryce, published in the Deport for 1883, of the Provincial Board of Health, of which he is the Secretary :— ‘4 The solvent power of water enables it to hold much mineral water in solution, while, as we know, much organic matter may be either dissolved or suspended in it as well. . . . Waters from limestone take up not only lime but often contain the products of the decay of organic material which have, in the shape of fossils of plants and animals, been enclosed in it. Similarly, wells which receive their waters from soaking through a surface soil or a sub-soil rich in organic matter, whether animal, from excreta and refuse ... or vegetable from the decaying roots of plants in the soil—often contain abnormally large quantities of organic material. . . . Such is the condition . . . present in very many of the waters of our Canadian towns, where no thought is even taken of the few simple facts which must convince all that sewage ... is continually percolating towards the wells. . . . Experiments carried on by the National Board of Health, of the United States, have shown that water percolating through 120 feet of pure sand in a tube does not lose all its suspended particles and bacteria.* But one important fact is, that different forms of organic materials supply food for different forms of bacteria, while the unfortunate fact remains that it is the bacteria similar to those found in the blood of patients affected with some contagious disease which develop in waters contaminated with sewage.’’ 30. In the report for the current year of the New Hampshire Board of Health, Hon. C. A. Downs discusses this question and gives the follow¬ ing valuable information :— 44 The popular belief is that water is purified by passing through the soil while the soil has power to purify foul water to a large extent, yet after a time it loses that power. x4t first it detains the impurities mechanically, but these impurities increase as the filthy water continues to enter the soil, till it becomes saturated with them and will no longer retain them. Moreover, this filth, so deposited, begins to decompose, and water passing through these saturated strata, instead of being purified, acquires an additional foulness beyond that with which it entered the soil, so that the agent relied upon for protection becomes the source of danger, t 1,4 Another source of water contamination has generally escaped notice and consider¬ ation. The foul water from many sources poured upon the soil deposits its filth ; this decomposes and sets free noxious gases, which traverse the pores of the soil in every direction. These gases mingle with the pure water of the soil and become a source of contamination. * Bacterium {pi bacteria) very minute organisms which appear in organic infusions after expo¬ sure to the air. f These remarks equally apply to the use of filters. In regard to the use of filters for water, Dr. Oldright, in the Report of the Ontario Board of Health for 1883, says:—“One thing the teacher should look after for himself and the pupils—that is, the condition of the filter. Filters are often used for months, and even years, without a change of their solid contents except by the addition of a large amount of organic matter retained in the fi ter, which becomes a source of danger.”