And again it does not give us, nor do we yet have, except by means of the microscope-which every one of us is not able to use on all occasions-an opportunity of knowing the presence or absence of certain microbes which are now beginning to give us a great deal of alarm, as we are able to know that they are a source of disease. I merely mention this fact, sir, so that those who may have noticed the exhibition of my friend (Dr. Lee) may not feel that we have gotten all that we may require in order to test the purity of the air. Dr. LEE. I wish to announce that I have received letters of regret from the following persons: Preston H. Bailhache, U. S. M. H. Service, San Francisco. Dr. Fred. Cross, Kingston, Pa. Hon. J. K. Newell, Wyalusing, Pa. Hon. John B. Donaldson, Canonsburgh, Pa. Hon. Geo. W. Neff, Masontown, Pa. Hon. James W. Walk, M. D. Philadelphia, Pa. Hon. G. M. Wherry, Shippensburg, Pa. Hon. John Donahue, Philadelphia, Pa. Hon. Lafayette Roland, Pa. Hon. W. H. McCullough, Tarentum, Pa. Hon. Chas. Moore, Pottstown, Pa. Hon. P. S. Weber, Du Bois, Pa. Dr. W. J. McKinnon, York, Pa. Hon. Geo. S. Wood, Muncy, Pa. Francis Cole, Arendtsville, Pa. Hon. J. B. Showalter, M. D., Millerstown, Pa. Hon. W. R. Swartz, Duncannon, Pa. Hon. H. W. Brown, Adamsville, Pa. Hon. W. McK. Williamson, Huntingdon, Pa. On motion adjourned. Hon. SECOND SESSION. The Convention was called to order by President Metcalf The PRESIDENT. I now have the pleasure of introducing to you Col. P. Roberts, who will read a paper on the future of our rivers as sources of water supply. THE FUTURE OF OUR RIVERS AS SOURCES OF WATER SUPPLY. By Colonel THOMAS P. ROBERTS, Modern civilization has made it possible for a much greater density of population, in some portions of the earth, than could have existed on the same areas in ancient times, or than was possible, even at the dawn of the present century, before the advent of the railroad and the steamship. It certainly would not have been possible in ancient times for inland cities the size of Paris, or Berlin, to have existed, and it is believed, by local political economists, that the population of Pittsburgh and Allegheny county, now somewhat over 500,000, could not be supported This little arrangment has been contrived for that purpose by a Ger by the surrounding country within available reach by the old time system of wagon transportation. As it is now, the products of the entire continent can be made available at any point, and cities are springing up entirely regardless of the capacity of the country about them as food producers, so that while the question of food supply for our cities is a matter of little concern, we are not so fortunate, in the case of many of them, as regards their water supply. It is indeed, remarkable, that the question of the supply of good drinking water for millions of our population should have become a problem of importance, before any alarm is experienced concerning the food supply, nevertheless, such is the fact. The trouble, of course, does not originate from an actual shortage of water, so far as volume is concerned, but arises from the new ways of living and supply of artificial wants. Water in enormous volumes is so essential, in many branches of the arts, and refuse, or waste, returning from the manufactories to the streams is so great, that we are simply spoiling our rivers as sources of a pure water supply. Many of the minor streams have been absolutely unfitted for any use, and while in such cases, where the pollution comes almost wholly from manufacturing establishments, such as coal washers, etc., it may bode no evil to public health; there are cases of others which create just cause for alarm. It is to be remembered further in this connection, that the sewerage system is just dawning upon legions of the smaller cities. Worse than manufacturing refuse, is the modern system of city water supply and sewerage, as in Pittsburgh, for instance, where the water daily furnished amounts approximately to two hundred and thirty (230) gallons per capita.* The writer may be wrong, but has sometimes thought that the common notion that the liberal use of water in our great cities is indicative of cleanliness, is a popular delusion. Every one recognizes the great convenience of street sprinklers, bath tubs, drains and sewers, in fact we have come to regard them as necessities; but too frequently the very person who will subscribe for water bonds, and spend hundreds of dollars in piping his premises, considers himself defrauded when assessed for sewers, and slams the door in the face of the first sanitary engineer who criticises his plumbers work. A meter system for water in our cities, would no doubt, be the means of closing leaky spigots, *This is inclusive of a number of private pumping establishments which supply several millions of gallons daily to manufacturing establishments. In the aggregate there is pumped fully 55,000,000 gallons of water daily for Pittsburgh, (exclusive of Allegheny), or about 230 gallons per capita. No other city in America uses more water in proportion to population than Pittsburgh, excepting perhaps New York. Fittsburgh, however, forms no exception to the general rule of cities of a ratio of increase in the demand for water much in excess of the growth of their population. and thereby, in that one item alone save half the wastage of water, and while it would be a good thing, financially speaking, its effect in reducing the contamination of our rivers would likely be small. In the city of Rio de Janeiro, until recently, the water supply for upwards of 300,000 people, came from the mountains in an aqueduct the capacity of which would have been insufficient for the supply of a good sized ward of an American city. There were a few public fountains, and from these the water was carried on the heads of the slaves to the dwellings. Under such circumstances bath-tubs, sinks, drains and sewers, could not exist; while the universal rule for closets was the dry earth-or closed jar systememptied nightly in the harbor.* Still the better parts of that city, so far as general cleanliness was concerned, compared favorably with the best parts of our average American cities. There were "slums" in Rio but the dirt about them was dry, excepting, we should add, during several months of rainy season ; but such things as "festering gutters," and, of course, sewer gas, and defective traps," were unheard of terrors. It would, however, be folly to oppose the modern system of liberal water-supply, now so generally adopted in American cities, but nevertheless it will not do to forget the responsibilities which devolve upon us in our wholesale use of water.† It is well established that moisture with warmth afford the requisite conditions for rapid propagation of many forms of microscopical life, hence the opportunities for the development, and transplanting, of the organisms, is vastly enlarged where water is carelessly used, and yet with a full knowledge of these facts, we permit our creeks and rivers to become the depositories of the filth and rubbish of our cities, in the sublime faith that by dilution with uncontaminated water, oxidation *It is rare that an epidemic of yellow fever in Rio leaves the shipping, or the immediate neighborhood of the shores of the harbor. It would occur to the writer, who spent several years in the neighborhood of Rio that the garbage furnace system, if introduced there, might play an important part in mitigating the yellow fever epidemics. It is stated as a fact that the "Point district" of the First ward of Pittsburgh, which is wholly without sewers, and where the population is very dense and confined chiefly to miserable tenements, has never experienced any serious epidemic of disease, while very serious, and sometimes unaccountable, epidemics of typhoid fever and cholera have ravaged other portions of the city served more or less perfectly with sewers. However, the case at the "Point " is somewhat peculiar; it is supposed that the river floods, which may occur several times during the year, by infiltration through the alluvial substratum dilutes, and carries off, with the decline of the waters, all the soluble impurities. In other parts of the city and in Alle. gheny, however, the infiltration of flood waters through the sub-soil is sometimes followed with sickness. It would not be safe to infer that the health of the Point district might be worse with sewers. Sewers, of course, mean more perfect drainage and multitudes of instances, could, no doubt, be cited where their construction has been followed with the best results. and other natural operations, they will become innocuous as a vehicle for the propagation of disease. Air and sunlight accomplish wonders for the benefit of the human race, but our knowledge of nature's processes are so imperfect that we are apt occasionally to make fatal mistakes in relying too much on her generosity. The vast number of innocuous forms of animal and vegetable life which enter our rivers from the sewers, may bring in themselves the means for the destruction of germs which accompany them, known, or suspected of being, capable of working an injury to human beings. This phase of the question has some argument for support-but all the desired facts, are probably not determined. There will always be a chance, one would think, for stray pathogenic germs to be pumped back to the water works, or consumed, by boatmen or others. It should rather be a warning for us when we find our streams stocked with animalculæ, and developing rapidly on the food supplies which it may contain, that the conditions are favorable for some wolves" among their numbers to be concealed in ambush-we certainly should not depend on them destroying each other. In 1866, or 67, the late distinguished Prof. Joseph Henry, advised the introduction into this country of English sparrows because of their known insectivorous habits. He wrote this too from the same institution which contained Spencer F. Baird, as famous then, as an ornithologist, as he was later as an ichthyologist. He was perhaps led into the mistake because the birds lived in a country where "good meals" were beyond their "purse," and were accordingly compelled to forego the gratification of their really omniverous tastes. So we might be sometimes deceived in our microscopic "oceans," and led into error when seeing one of the protozoa making dinner of a defunct micrococci. We do not want any forms of life, animal or vegetable, in our drinking water. We may know enough concerning them not to have misgivings in regard to the development of those species originating in pure water; that is to say, water uncontaminated with sewage matter, but their presence is always positive evidence that there is pabulum, as well, for others of which we have reason to dread. The writer disclaims any pretentions to scientific acquirements in chemistry, or microscopical research and their pathological bearings, yet with the highest respect for the learned specialists, who are laboring in these fields, he believes they have not as yet devised any convenient or comprehensive system of standards for determining when the water of our rivers is unfit to drink. The tests for albumen and nitrates, seem of late, to be neglected at least in our local examinations too much for microscopic work, and both the microscopists and the chemists are handicapped by doing all their work in their laboratories with sealed, and unlabelled, specimens of the water. In a neighboring city there was, recently, an illustration of the imperfection of this blindfolding method, where samples of the river water from opposite the city, were compared with water taken from a point, many miles above, where no sewer exists. It so happened that the water from above the city having been found to contain specimens, we believe of entozoa, was pronounced to be more contaminated than that below. It is clear that the microscopist would never have asserted, without qualification, such a thing had he known how, and where the samples were gathered. The finding of a single objectionable specimen in the presumably purest sample would have suggested to him a more laborious examination of the other sample, and under high powers, for the throough examination of water requires diligent application and protracted labors. There is needed in the study of the hygienic qualities of river water besides scientific acquirements, practical knowledge of the stream. The facts regarding the width, depth, normal and least velocities, volume of discharge of the river, position of sewers, and the character of their contaminations should all be studied, with their relative bearings before decisive opinions are expressed. The public are sometimes needlessly alarmed by the reports of the specialists, when not thus supplemented by a consideration of all the facts. All this has little to do with the future of our rivers as sources of water supply, but as all know they are continuing to become each year, more and more impure, there is little to be said on the subject save to reiterate the fact. Regarding the quantity of sewage waters returned to our rivers, Dr. Parkes, years ago estimated the amount of absolute sewage it contained to amount to about 1,000 lbs. per annum for each inhabitant. No account, however, being taken of the true sewage which should be apportioned to animals, kitchen waste, slaughter houses, tanneries, etc., and that contributed by the streets. Three thousand pounds per annum, or say nine pounds of absolute sewage per day, for each inhabitant, is nearer the truth. The daily waste of water, approximating onehalf of the total supply, the other half lost by evaporation, which would make, say, for Pittsburgh, 115 gallons, is mixed with the ninepounds, or nine pints of absolute sewage, and in case of rains the dilution would be many times greater. We might pause here to ask is not this a good thing to dilute the sewage? Well that is one of the prob lems. We know that no quantity of white paint mixed with black will render the latter pure white-and that a very little black will go a long ways in discoloring a large quantity of white paint. It would seem a pity, therefore, to contaminate so much water-and also our streams, simply to get rid of this small quantity of real sewage-and yet, that is what sewers are primarily intended for. If Waring's system of separate conduits for house drainage and storm waters, is not yet a pronounced success, his ideas are, like those of the experimentors with the storage battery system for street car propulsion, in the right track, and |