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THE QUESTION OF PURE WATER FOR CITIES.
VITH a view to improving the purity of public water-supplies, in what di
rection are we to look? This question is certainly first in order, if it be s question. I think it is not usually treated as a question; that it is not usually considered; but that it is taken for granted as axiomatic, that of course we are to look to the sources of contamination, and shut them off.
But what are those sources ?
Well, first, the entire atmosphere, with all the exhalations and effluvia that can ascend by the method of diffusion or by the rarefying energy of the sun, and with all the comminuted solids that can be raised and down upon all waters by the force of ordinary winds, not to speak of cyclones.
Second, the whole deciduous material of organic life, animal and vegetable, perpetually strewn upon land and water, falling in the rain, rotting on the margins and in the channels of streams, and leaching into water-supplies from every inch of the habitable earth.
Third, in addition to the regular and constant course of death and decomposition throughout nature, the overwhelming organic débris precipitated upon land and water by the breaking up of the vast annual accumulations of winter, and by frequent extraordinary shocks or pestilent changes such as occasionally choke considerable streams with dead and putrefying fish that thicken both the water and the air with the products of their decomposition.
Fourth, the most energetic of all filth-producers and accumulators, man; as much worse than the total of all nature besides, in this respect, as his powers of mind, machinery, and organization exceed the resources of the inferior creatures, while at the same time unprovided with those automatic sanitative faculties that save unintelligent nature from self-destruction. He industriously accumulates large animals in great numbers, with vast products of cultivated vegetation, and concentrates all their refuse and decay, with his own, about his doors. He lines the banks of every stream with manufactories that work up all things in the mineral, vegetable, and animal realms of nature, and pour their changed refuse abroad on the valleys and streams. Worst of all, he accumulates himself, and propagates and packs himself, in dense masses enormously and endlessly growing by the side of all waters, until the perpetual off-castings of his enormous life overwhelm the sanitative powers of nature, and breed unresisted pestilence in water, air, and soil, as far as his encroaching multitudes extend their habitations.
Do we seriously propose to stay these combined and rising floods of impurity with our brooms ? Physical force is not given puny man to oppose cosmical forces like these.
Nature has a perfectly successful way to dispose of her own refuse and that of her own children. It is another thing to cope with the cumulative waste of crowded and artificial human life. This cannot be done by the forces of nature, of engineering, of law, or of all combined. The apparatus of nature is perfect as far as it extends ; but it is not concentrated on the lines of civilization, where the pestilent results of wholesale artificial pollution are assembled. Such concentration, therefore, is precisely what is wanting; the one thing needful, effec
tual, and practicable too, by scientific artificial means. We are to take the sanitative methods and agents of nature, adapt them to the changed conditions we have caused, and concentrate them on the concentrated impurity of our waters.
We must do this, because it is impossible to limit these excretions of civilization, or to make room for them outside, or to get along with them by any other method than that which nature has used hitherto with the refuse of the primitive world. We have before us, on the scale of the sparse primitive world, a model apparatus for the perpetual renovation of air, water, and soil to the perfection of wholesome and delightful purity. Nature could not keep out excretion, death, and corruption from these vital elements: no more can we exclude them, in the increasing proportions created by dense civilization, though our very best were done, as it should be, to stop all avoidable defilement. But nature could do something better; and so can we, in the same way: not bar out, but transmute for usefulness, the polluting waste, while daily renovating the vital elements to pristine purity and freshness.
To be more explicit: The rain-water, with the countless impurities it brings from the atmosphere and takes up from the filth of the earth, is first treated by nature with the metallic salts of the soil through which it percolates,-chief in importance those of the ubiquitous potassa and aluminous clay ; by which (as every chemist may have found by an imitative treatment) the soluble impurities are withdrawn from solution and coagulated, together with the finer suspended material, for exfiltration. Reaching the sandy sub-soil, filtration commences, and the coagulated impurities are left within reach of the long root-filaments of plants, by which the natural filter is kept cleansed; while the bacteria, whose tendency is to attach themselves, and to work upward rather than otherwise (if we may trust recent demonstrations), also remain in a region of sustenance and usefulness, or else perish infertile in the sterility of the deeper and denser sand. (The above takes place where the proper conditions for coagulation and filtration are combined, as they are not in all places: numerous instances having been noted where polluted, infected, salt-impregnated, or purposely qualified waters have passed through long reaches of sand without undergoing any perceptible change.--undoubtedly for want of chemical assistance from the soil.) A third and still further refining process is going on all the while by the intimate mingling of the diffused water with the telluric atmosphere, under increased pressure as the depths of the earth are penetrated, until, at great depths, the oxygenation of the water-increasing in a large geometrical ratio to the increase of pressureresults in that extraordinary refinement and vivacity for which certain deep-well and spring waters are famed.
To defend our surface-water supplies from sewage and the filterage of privies, stable-yards, and graves, is a most important duty, and ought to be a plain one, to intelligent purpose instructed by natural science. But, pending this not-soon-to-be-accomplished task,-or even granting this accomplished, to go on drinking all the vast residue of unavoidable pollution, with all the probable and possible germs of disease and the certain quantum of reptiles and parasites, when cities by the score are actually rejoicing in full supplies of water filtered from streams to the highest known standard of purity,—to go on doing this in the face of present fact and science, I must pronounce a crime for which ignorance is now no more excuse than indifference.
Let facts speak for themselves—and he that hath ears to hear, let him hear at such places as Long Branch, Atlanta, Somerville, N.J., and a hundred others. Let the reports-official, not ex parte-of most of the prominent experts in the chemical and biological testing of waters in the United States, interpret the testimony of the waters in such places as I have referred to, showing, as they do, foul waters constantly purified to the sanitary chemical standard, which is unknown in any surface-water supply in the world, and their swarming microbes of every kind eliminated down to a half of one per cent. (as shown by the investigation of the Providence Health Department), or to an infinitesimal quite undiscoverable by the culture-test, as reported by Professor Long, of Chicago, and Professor Kedzie, of the Michigan State University. These cumulative confirmations leave nothing to be demanded further in proof of the practicability and the duty of purifying all public water-supplies, whatever their condition, forth with to an absolutely unimpeachable sanitary standard.
Nothing remains but to make the public understand the true and inexorable conditions of the achievement.
These conditions are nothing more nor less than a strict scientific reproduction in substance of the processes which science comparatively recent has traced out in the natural renovation of water, universally contaminated, to the crystal perfection of the finest springs.
These processes are precisely four. First, the chemico-mechanical action of the salts of the soil, -chiefly the ubiquitous alumina or common clay,-withdrawing from solution the dissolved organic matter which otherwise no depth or density of filtration can ever touch, and flaking together in their adhesive residuum the matter thus rendered tangible, with the microbes that flock with it, and other particles in suspension which are often too minute (as in coloring-matters) for exfiltration. Next, a compact and deep filter-bed of fine sand, --not forgetting the carbon whick all soils supply. Then, a continuous and perfect cleansing of the filter-sand from the arrested impurities, such as is kept up in nature by the greedy root-filaments of plants. Finally, a forcible and prolonged oxygenation of the approximately purified water, under deep pressure analogous to that which nature gives to her finest product in the profound recesses of the earth.
To recognize these conditions is one thing; to realize them is quite another. Water-purification has been bafiled for generations, and is still baffled in some places where it is vigorously pursued, by the want of mechanical devices competent to secure the last two objects,-perfect and continuous filter-cleansing, and forcible oxygenation.
Stone or porcelain filters are valuable for private use, because the exfiltered matters are held on the surface of the material and can be easily scrubbed off. But in a granular filter of large size it is no easy matter to scour every grain clean of the tenacious slime that accumulates on all surfaces that detain the impurities of a foul water-supply. This problem is emphatically the pons asinorum of all would-be water-purifiers on the large scale. The difficulty is to put through the filter a sufficient scouring energy of water-pressure without washing the sand out into the waste-pipe. This necessity has but recently been appreciated and met successfully, and in two ways: either an upper chamber is added to the filter, for the liquefied and tormented sand to be discharged and scoured in, and whence it may subside again into its bed when thoroughly cleansed; or else the requisite force of water is applied to parts of the sand in succession. No large filter has ever yet been kept clean or efficient but in one
or the other of these two ways; and unless so kept constantly and thoroughly clean, it is worse than nothing. Any pretence of getting along with the light, oozy rinsing that is practicable all at once in a single-chambered filter, or with a superficial wash in the top sand, is a “a mockery, a delusion, and a snare." The knowledge of these things is the fruit of vast experience and expense in the past, and is as well established as any human knowledge can possibly be.
It should not be necessary, but perhaps it is, to point out that the upward action of a jet of water, which loosens the sand, is the only way to wash it, and the downward pressure, which compacts it, is the essential for efficient filtration. It seems incredible that even a theorist without experience could invert both of these self-evident principles and rush enthusiastically into “upward filtration” and downward washing. Yet such is a fact, and it is reported that a very big concern in the city of Philadelphia will engage in the idiotic experiment.
The last point is aeration. Too much has been claimed for it as a means of oxidizing the gross filth of streams; but as a finishing process for giving the highest refinement and vivacity of spring-water, it has the sanction of nature's example, and can be applied in the utmost perfection by artificial means.
For this, also, it is important to show the public how not to do it. The crude expedient of forcing air into city mains, to hammer its way, with great destruction of joints, to the house-faucets and hydrants, blowing out explosive spurts and spray in place of water, has been tried and got rid of in a number of places, notably Philadelphia and Chicago, and yet is still urged upon inexperienced communities. A harmless method, in behalf of wbich a good deal of enterprise is expended, is to force air into the bottom of the distributing reservoir, from which it mounts in bubbles like a balloon, and instantly and entirely escapes at the surface. Pressure unconfined and upresisted is not pressure, and compressed air released in an open reservoir is little less than free. The bubbles that seem to the untutored eye to be aerating and exhilarating the water are simply getting out of it, leaving nothing behind.
Here, again, nature is the inventor's true instructor, and a deep well affords the best practicable analogue to her far-underground laboratory for aeration under pressure. I know of no other effective apparatus as yet devised, but a pipe well, say one hundred feet deep, into which the water-supply falls, carrying with it a copious rush of air through a sort of Sprengel injector, and returning up from the bottom by a rising pipe connected with the filter or reservoir. Under a pressure of three atmospheres at the bottom of the well, the oxygen of the air is largely absorbed in excess of the nitrogen, and the latter freed escapes, while the oxygen remains to some extent and for some time in solution, and, being comparatively undiluted with nitrogen, acts rapidly and powerfully for the destruction of organic matter and for the sanitation of organic germs. For an example and test in practice of this novel and powerful process of aeration, in combination with the other conditions above stated for perfect water-renovation on the large scale, the best public water-works at present are those of Long Branch, N.J. The results, scientifically stated, are as follows. Chemical analysis by Prof. Norton for the Massachusetts State Board of Health: Albuminoid ammonia (principal indication of organic contamination), 0.0176 part in one million parts of water before purifying; after purifying, 0.006 part,-a reduc tion of about two-thirds of the impurity from a water already near to the safety standard, bringing it down to fifty per cent. purer than the safety standard
Biological tests by Dr. Charles V. Chapin, Superintendent of Health for the City of Providence, R.I., thrice repeated : Organisms in 1 cubic centimetre of water before purifying, 258; 298; 248 : after purifying, 5, 2, and 3, respectively.
William C. Conant.
THE SEAMY SIDE OF LITERATURE. .
Any one who wishes to become acquainted with the seamy side of literature should examine the batch of manuscripts received daily by some periodical publication. After passing through the several stages of amazement, irritation, and disgust, he would probably arrive at the conclusion that people who find they are incapable, through lack of brain-power, of doing anything else in the world, think themselves amply qualified to turn author. They would not attempt to compose a symphony, or paint a picture, without previous instruction; but as for writing, -well, all that is necessary is to invest in pen, ink, and paper. With this capital, they are ready to set up in the business of literature. Allured by the glittering fairy-tales of the paragrapher, they do not see why they, as well as others, should not amass wealth and laurel wreaths. Their artless unconsciousness of their own incapacity-the serene confidence with which they send forth their effusions--would be touching, if it were not such an oft-told tale.
Only the examiner of manuscripts can know the baleful ingenuity of those who take an enemy into their hands to steal away their brains,—the Protean forms their ignorance and folly assume. It seems as if there must exist, somewhere, a sort of literary Domdaniel whither they repair, at stated intervals, to become wise in all manner of editor-torturing devices. Perhaps it is some limping verses,-of so doleful a cast that they may be said to have one foot ja the grave,--sent by a lady who states that they are “from the pen of a beloved sister of my friend Mrs. Briggs," and holds out to the editor the bright hope that he may be an humble instrument in “the development of a future genius." But the editor, being a cautious man, is not prepared to take any such risk. Another sends a rambling narrative relating, with much circumlocution, the life, sufferings, and death of “one of nature's noblemen who everybody called uncle;" saying, in the accompanying letter, “I hope some day to make a name for myself by which I may be able to earn some money with which to aid my mother, fix her home, which is going to rack, and do something for my sisters and one thing more which I rather not write, being so secret.”
A poet, clearly of German nationality, sends an “Ode to the Western Maid," and writes concerning the inspiration thereof, “ There is in this town such lovely joung Lady, and as she is of the excellent ladies of the West a true type, I was inspire by the Muse to compose the poem. It may attract the attention of foriegners to the rich resurses of the Western land, and as the graceful, noble, unsurpassed maidens are well deserving the highest praise, I take the occasion to recomend them. I have written also other poem,-namely, Praise of the Teacher Lady, and Praise of the Typo Lady.” Another bard, with a name that indicates Polish origin, thus expresses himself on the subject of the birth and development of his genius : “ Having been a lover of poetry and poems, I spent all my moments in essaying to write poems of divers kind. I did write and compose a few, but upon reading them over and again they seemed to loose their