of 81% in the deaths from typhoid fever, but also a marked reduction in the general death rate. His computations clearly indicate that where one death from typhoid fever has been avoided by the use of a better water, a certain number of deaths, probably two or three, from other causes have been avoided. It is a difficult matter to explain how water is connected with the deaths other than those from water-borne diseases, yet when we consider that water enters into the composition of the human body to the extent of 63%, we are in a position to appreciate the sanitary acumen of Aristotle when he wrote in his Politica: "The greatest influence on health is exerted by those things which we most freely and frequently require for our existence, and this is especially true of water and air."

AVERAGE LENGTH OF HUMAN LIFE

Professor Finkelnburg, of Bonn, estimates that the average length of human life in the sixteenth century was only between 18 and 20 years, and that at the close of the eighteenth century it was a little over 30 years, while today it is between 38 and 40 years-indeed the span of life since 1880 has been lengthened about six years. No two factors have contributed so much to the general result as the improvement of the air we breathe and the water we drink. Indeed, we have ample evidence that with the introduction of public water supplies and sewers the general mortality in numerous cities during the past fifty years has been reduced fully one-half, the good effects being especially shown by a marked decrease in the number of cases of typhoid fever, diarrhoeal diseases, and consumption. The vital statistics of Great Britain furnish the proof," and our experience with American cities confirms this conclusion.

a The following table shows the death rate from certain diseases per 10,000 of population in English cities before and after the introduction of sanitary works (see Cameron, A Manual of Hygiene, 1874, p. 129):

EFFECTS OF PURE WATER ON THE NATURAL GROWTH OF THE POPULATION

The mortality of London between 1660 and 1679 was 50 per 1,000 of inhabitants; from 1680 to 1728, including the period of pests, it was 80 per 1,000; between 1729 and 1780 it was still 40 per 1,000, since which time it has steadily decreased to 15.1 per 1,000 in 1905.

The death rate in the city of Berlin has been reduced from 32.9 in 1875 to 16.4 in 1904; in Munich from 41.6 in 1871 to 18 in 1906, and in Washington from 28.08 in 1875 to 19.25 in 1907.

The death rate in the city of New York in 1804 was 28 per 1,000; from 1850 to 1854 it was 38 per 1,000; while in 1906, in spite of the density of population, it was 18.9 per 1,000, practically a reduction of 50%, which according to Walter F. Wilcox" of Cornell University, means a saving of something like 46,000 lives each year in that city alone.

The mortality in the registration area in the United States has been reduced since 1890 from 19.6 to 16.2 per 1,000 in 1905. Taking the Census figures of a population of 33,757,811 in the registration area as a basis, the number of deaths in 1905 was 544,533; whereas at a rate prevalent in 1890, they would have been 662,654; a reduction of 17.8% and a saving in one year of 118,121 lives. If the same ratio is applied to the entire estimated population in the United States of 82,574,195 the saving of human lives during 1905 alone would be over 290,000.

SELF-PURIFICATION OF STREAMS UNRELIABLE

We would not think of establishing a vicious circle between our mouths and the drainage of our houses and stables, and yet practically we have suffered this to be done upon the assumption that rivers purify themselves. A certain degree of purification is possible by natural means, such as dilution with unpolluted water, deposition of suspended matter, the agency of aquatic animals and plants, the bacteria of nitrification, the destructive influence of sunlight upon germ life, and the chemical affinity of certain bodies. These factors are calculated to purify waters, provided we give them a chance. This may still be true in very sparsely populated regions of our own country, but with increasing settlements. the pollution of our streams will become continuous from their sources to their mouths, and river water to which sewage gains access must be considered as dangerous for drinking purposes.

ACTION REQUIRED IN THE INTEREST OF PUBLIC HEALTH

One of the most pressing needs is an investigation into the pollution of water supplies when such pollution affects or threatens to affect the sanitary condition of the people of more than one State, because the in

a Monthly Bulletin New York State Department of Health, March, 1908.

dividual States are powerless to protect themselves against the misdeeds of their neighbors. Mr Bartholdt's bill for the appointment of a river pollution commission, first introduced in 1896, has not yet become a law. England enjoyed the benefit of such a commission as early as 1855, and in order to prevent, remedy, and remove the danger of polluted water supplies adopted a comprehensive system for the disposal of sewage and of water purification, the fruits of which have already been referred to. Sanitarians have maintained for years that no community or individual has a right to pollute streams used for public water supplies any more than a man has to poison his neighbor's well. The legal aspects of water pollution were presented by Dr J. L. Leal" in a paper read before the American Public Health Association, 1901, and it is gratifying to note that quite a number of our States and Territories, though in various degrees of effectiveness, have sought to protect waters used for public supplies within their boundaries. While much commendable progress has been made, more remains to be done, especially as regards uniformity of legislation and adequate protection of interstate waters. All that is needed in this country is a correct appreciation of the dangers of interstate water pollution.

The principles of common law as to waters have been appreciated by some of the nations of Europe. Thus the inhabitants of a town in Belgium suffered from the effects of a river polluted by the French, and the French government not only compelled the offending city to dispose of its sewage by irrigation but granted a subsidy for this purpose.

METHODS OF SEWAGE DISPOSAL

After determining the extent and dangers of river pollution, the remedy can and should be applied. This remedy is not only of interest to the sanitarian but also the agriculturist and consists in the adoption of a proper method of sewage disposal, including harmful industrial wastes.

The best method so far proposed is sewage farming, or irrigation. The British Royal Commission as early as 1876 approved it; in fact this method has been successfully used for centuries on the hot plains of northern Italy and in Spain, and will also have a very promising future in the West where every drop of water is needed for irrigation.

The city of Berlin purchased about 20,000 acres of land and, notwithstanding the enormous outlay of a little over $3,000,000 for the land and over $10,000,000 for the sewer system, operates these farms at a net profit

a Dr Leal in his paper divided the States and Territories into five classes according to the nature of their statute law upon water pollution. Extracts of a more recent review by Edwin B. Goodell, which brings the subject matter up to August, 1905, is appended (pages 260-263). For complete digest consult Water Supply and Irrigation, Paper No. 152, U. S. Geological Survey, 1905.

of about $60,000 per annum. The city employs men condemned to the workhouse as laborers at the farms, and practically converts vagabonds into a producing class, with a fair prospect that many of these individuals will continue their honest efforts to become self-supporting citizens. Moreover the old manor-houses of the individual farms are utilized as country homes for convalescents, and thus the beneficent effects of this system are felt in more than one direction.

Heretofore it has not been considered necessary to prevent the pollution of rivers affected by tide waters. Dr Conn of the Wesleyan University, in 1894, however, traced an outbreak of typhoid fever to raw oysters which had been fattened in a place where they were liable to contamination by typhoid-infected sewage, and since then numerous instances have been reported elsewhere. It has been shown that typhoid fever germs remain viable in oysters from fourteen to thirty days, and the medical officer of the local government of England in the twentyfourth annual report points out the danger of many of the oyster beds from the sewage pollution on the English coast, all of which indicates that even this newly discovered source of danger must be guarded against. On the whole we may conclude that sewage farming for economic reasons should be recommended for all localities where the grade will admit of the sewage being carried to lower lands. In sections of our country not adapted to farming and where land is scarce and expensive, purification of sewage by intermittent filtration should be adopted; in communities where land is so scarce that even intermittent filtration is impracticable, chemical precipitation or sedimentation; the bacterial or septic tank with Dilden's bacteria filters should also be considered. Space will not permit details concerning the different methods.

It is a matter of great satisfaction to know that within the past 15 years over one hundred communities in the United States have established plants for the disposal of sewage. In 1901 I published a tabulated list of 93 communities. In 1904 Mr Geo. W. Fuller" published a list of 114 towns and cities of over 3,000 population, which is appended (pages 264-271). A summary of types of sewage purification follows:

a See Sewage Disposal in America. Transaction Society of Civil Engineers. International Engineers' Congress, 1904, Paper 64.

The first attempt in the establishment of a sewage farm in this country. was made at the Augusta (Me.) State Insane Asylum in 1872. Among the more prominent and successful sewage farms may be mentioned Brockton and South Framingham, Mass.; Bristol, Conn.; Plainfield, N. J.; Altoona and Wayne, Pa.; Pullman, Ill.; Hastings, Nebr.; Colorado Springs, Colo.; Salt Lake City, Utah; Helena, Mont.; Phoenix, Ariz.; Fresno, Los Angeles, Pasadena, Redding, and Santa Rosa, Cal.

PURIFICATION OF PUBLIC WATER SUPPLIES—RESULTS ACHIEVED

The primary object of sewage disposal is the prevention of water-borne diseases, although the economic aspect should not be lost sight of, especially since it has been shown that this method alone can not be relied upon, as instanced by the cholera epidemic at Hamburg and the typhoid fever epidemics at Cumberland, Plymouth, and elsewhere, where the dejecta of a single patient were sufficient to cause the mischief; hence prevention of river pollution must be supplemented by filtration of the water supply on a large scale.

The diagram on page 259 shows the relation between typhoid death rates and various water supplies, grouped according to the character of their source, and shows conclusively that the European cities who not only prevent pollution of rivers but also filter their water enjoy the lowest typhoid fever rates.

In conclusion permit me to say that while we have reason to be proud of manifold achievements, we have not kept pace with other countries in matters relating to public health. I am profoundly grateful for the opportunity of discussing a subject of vital importance to the strength of this Nation. Progress has crowned our past. Let our conduct raise no blush on the cheek of posterity. Let us hand in hand, with heart and tongue, join in promoting the welfare of the American Nation by the conservation of health and life and all of our natural and wonderful

resources.