35.9%. In 1896, according to the Manual of American water works (last edition 1897), the number had increased to 3196, and since, in many instances, a single plant furnished water to several municipalities, the total number of cities and towns thus furnished, either partially or wholly with public watersupplies, was 3942, the population of these places (by the census of 1890) being 41.6% of the population of that year. The rapid increase of this important work in some of the states is marvelous. Only 5 cities west of the Mississippi river were furnished with public water-supplies before 1860, but in 1896 there were 1011 cities and towns having public water-supplies west of the Mississippi, and many more were in contemplation. In the 2 states of Nebraska and Kansas alone there were only two existing public water-supplies previous to 1880, while 180 have been introduced in the same states since 1880, most of them being in towns of less than 3000 inhabitants. During the last quarter of a century, several very extensive schemes for supplying water to large populations have been inaugurated. Among them may be named the extension of the water system of New York city, by the enlargement of its tributary water-shed, and the construction of the Croton dam, with the Croton lake and the Jerome park reservoirs. The enlargement and improvement of the Chicago water-works, by the extension of the water intake to a distance of 4 miles into Lake Michigan, this scheme having become necessary in consequence of the increasing pollution of the water-supply by the drainage of the city. A new supply was also planned for the metropolitan district about Boston, and is in process of construction. This scheme will afford an ample supply for a population of about 2 millions when completed, and is capable of further expansion. Greater attention has also been given during the past 20 years to the subject of water purification, and measures have been undertaken, and in some instances completed in several cities, for the purification of their water-supplies by means of filtration. Among these special mention may be made of the city of Lawrence, Mass., which had for about 20 years drawn its supply directly from a river which was polluted by the sewage of several hundred thousand inhabitants living above the intake of the water-works. Typhoid fever had increased in the city to alarming proportions. But after the introduction of the filtration system, the death-rate from this disease was reduced to less than one tenth of its former size, and has continued to diminish from the year after such introduction of the new filtering plant. Similar measures are being taken in other American cities. The following table presents the statistics showing the growth of public water-supplies in the United States during the past century: GROWTH OF THE WATER-WORKS IN THE UNITED STATES The following table presents by groups the percentage of the population supplied with public water in each of the states in the Union in 1860 and in 1896: The charts between pages 36 and 37 also illustrate the same groups in a graphic manner. See also the statistical table in appendix I, columns 7 and 8. SEWERAGE AND SEWAGE DISPOSAL Closely related to the subject of water-supply is that of sewerage and sewage disposal, since the sewage consists of the water of the public water-supply, with the addition of such household filth and manufacturing wastes as may be added to it by the population. Both are sanitary necessities of great importance, but the public water-supply is usually introduced long before serious thought is given to the question of sewerage. It is for this reason that the percentage of the population living in sewered towns is very much less than that of the towns furnished with public water-supplies. The percentage of people living in sewered towns in the United States in 1896 was 28.71, while the percentage of the total population living in towns having public water-supplies was 41.6.2 The number of cities and towns which had introduced systems of sewerage3 in 1896 was 822, or less than one fourth of the total number of cities and towns furnished with public water-supplies. The methods of disposal are various, and are necessarily 1) This figure is probably incorrect for the following reasons: the essential information for an authoritative statement on this subject was compiled from the manual of American water-works, this being the only work in which such information could be found with a fair degree of completeness. The information in that work was obtained by means of circulars issued to the authorities having the water-works throughout the country in charge, and may be relied on as accurate so far as water-supplies are concerned, but that which applies to sewers was obtained from the same water officials. In very many municipalities the watersupplies and sewerage systems are under the control of separate authorities. Hence, information obtained from one department relating to another department can not be considered as accurate as that which it provides relating to its own affairs. In two states it was found possible to correct the percentage given in the table, by means of lists existing in those states. For example, in Massachusetts, the addition of towns and cities having sewers, not mentioned in the manual, increases the percentage from 63.3 to 73.5, and in New Jersey from 63.6 also to 73.5. It therefore seems probable that from 5 to 10%, or more, may reasonably be added to the figures given for each of the states in the table on page 43. We have preferred to present in the table only such figures as could be compiled from published statements, without attempting to give approximate estimates. 2) See chart facing page 43, and table on the same page for further details. 3) The term "system of sewerage" is here intended to apply to those systems which collect household sewage, but not to those which are constructed to receive storm water only. |