cleaner costs in the neighborhood of $300.00. If these are installed at this expensive price it evidently answers the question that they pay for themselves.

Regarding the other speaker's remarks I did not mean to depreciate the horizontal return tubular boiler. Of course, the horizontal return tubular boiler is practically the only boiler for small plants on account of its first cheap cost, for although it is limited in size to about 125 horse power it can be installed for about $12.50 per horse power. Any water tube boiler would be double that in cost. That is why horizontal return tubular boilers are installed in preference. The reason they are more dangerous is because it is hard to keep them in proper condition. You can not get at the surfaces to keep them properly cleaned. Then the amount of water contained in such a boiler in one compartment has a great deal of energy, which if suddenly liberated will cause a very disastrous explosion. In the water tube boiler the water is not so great in volume and so we do not have such disastrous explosions in water tube boilers.

Mr. Parks: I want to say in regard to soot cleaners that they pay for themselves and are well worth all their cost in any plant. I find one installed on a 100 to 125 horse power horizontal tube boiler is proving very satisfactory and efficient.

Mr. Merrill: I have a question in regard to the economy of different kinds of power. How does the small steam plant with the modern efficient boiler, using coal for a fuel, compare with the hydro-electric plant, or the purchase current from the hydroelectric plant at about three cents per kilowatt hour.

Mr. Fessenden: That I can also best answer by referring to some of the practices in the State of Michigan. For example the Commonwealth Power Company owns both kinds of plant; a number of waterpower and a number of steam. I notice in certain. localities, for example in Saginaw, Battle Creek, Kalamazoo, their steam plants are idle and held as reserve or insurance plants to insure continuity of service. That practically answers the question that is does not pay to operate steam plants as long as we have water power plants available. These reserve steam plants must, however, be serviceable and ready to put in commission should anything happen to the water power plant. This question

always depends on the cost of fuel. If the cost of fuel is high and water power close by; under these circumstances it would pay to operate the water power plant. If the reverse were true then the steam plant is best.

Mr. Parks: I understood Mr. Merrill's question was whether the small steam plant could furnish power in competition with large hydraulic plants.

Mr. Merrill: Yes, providing they can purchase it at three cents per kilowatt hour.

Mr. Parks: We find in our practice that question is largely one of quality or class of product. In other words, if the plant is turning out a product in which they can utilize the exhaust steam to good advantage, for heating and drying material, etc., then there is no question but what they can make power cheaper than the central station can furnish it. On the other hand if they have no use for their heat in exhaust steam in the way of drying material or heating, why it then is a question of locality to a great extent, whether the central power station can deliver the power at their switchboard at a price cheaper than they can make it. I think that they can make it even in small plants at less than three cents per kilowatt hour.

President Teed: I wish to appoint a nominating committee to nominate officers for next year, consisting of Messrs. H. E. Riggs, L. C. Smith and J. J. Cox, announcing it at this time so they will get their report ready for tomorrow's business meeting. The meeting will now adjourn until 7:30 this evening.

Adjournment.

of the Annual Convention was called to order on Tuesday at 7:30 P. M., and was devoted to the

Symposium on Sanitary Engineering

HENRY F. VAUGHAN

Member M. E. S., Chairman

President Teed: The first paper this evening on the program is by Professor W. C. Hoad, but as he was unable to get away, although he may possibly arrive on the 9:30 train, Professor Decker will read his paper. As to the discussion on these papers Mr. Vaughan requests that we leave the discussion until all the papers have been read so we can discuss them all at the same time. Mr. Vaughan has arranged this evening's program, and I am going to ask him to take charge of this part of the meeting.

Mr. Vaughan: Professor Decker will read the paper;

The Use and Abuse of Streams in Sewage Disposal

W. C. HOAD

Member M. E. S.

The relative importance of the different uses to which natural waters and waterways may properly be put is thus stated, in the progress report of the Special Committee of the American Society of Civil Engineers on a National Water Law:*

"Those uses of water which vitally affect the life and health of humanity have precedence over all other uses, through the operation of the inexorable laws of Nature. Next come those uses necessary to the pro

*Presented to the annual meeting of the Society, January 19, 1916; published in the Proceedings for December, 1915.

duction of food supplies; and after these, in order of importance, follow the application of water to the essentials and conveniences of civilization.

(a) The first use of water in importance and the one truly paramount, namely, that for the domestic or household requirements of man-one without which life itself must disappear-was not recognized as of sufficient consequence for consideration when the rights of navigation received their present prominence in this country. At the time of the adoption of the Federal Constitution, outside of New York City and Bethlehem, Pa., municipal or public water supplies appear to have been non-existent in America.

(b) The second use of water, in present importance, is that for the watering of livestock and the production of crops, upon which two factors the food supplies of the nation depend. The former of these applications is long recognized and well established, but the latter, now reaching its highest development in the vast irrigation systems of the arid and semi-arid States, is a use almost unknown in this country prior to the Civil War. Co-ordinate with this use, and as a necessary adjunct in many cases, is the drainage of lands rendered unproductive by an excess of water.

(c) The third in relative importance is the use of water in the disposal of city sewage, for, whether with or without preliminary treatment, the sewage from inland cities must of necessity be carried away and finally disposed of in natural waterways, which are a part of the great circulatory system of the country; and the right to the use of water for this purpose must be clearly recognized.

(d) The fourth use is that for manufacturing, and for the generation of power to be used in the production of the requisites of civilization. The former is practically inseparable from the domestic uses in an ordinary municipality, but the latter is a larger, more specific and more easily distinguished use and is commonly designated power development. Closely related to the above is the preservation of property by protection against floods and the regulation of the stream flow to this end, as well as with a view to an increased utilization of the water.

(e) The fifth use is that for the transportation of the products of agriculture and materials of manufac

ture, and for the convenience of travel, designated as
navigation.

Of the uses above noted, the first three are essen-
tially uses at large, in that their direct benefits are
shared by the community in general and with the least.
intervention of profit-making intermediaries. The last
two are essentially commercial uses, developed chiefly
for individual gain, and should be subject to the require-
ments of the former. All but the first should yield
to the rights of eminent domain exercised in favor of
those uses higher in rank."

The foregoing quotation sets forth clearly the idea of the profitable use of water, as distinguished from its mere preservation. It is based upon the fundamental propositions that the ownership of the water is in the public, and that the largest measure of public good will result from its largest beneficial use.

The ancient and primitive uses of a stream produced very little change in its character. To take out a few pailfuls for household purposes, to lead domestic animals to its bank to drink, to take fish from its waters or to float over its surface in a canoe, all these left the stream practically as before, undiminished in quantity and unchanged in quality. Such uses satisfied the needs of the people and were well adapted to the public welfare in those humid and well-watered countries from whose customs we derive the body of our common law. Under such primitive conditions it was quite in harmony with the public welfare that the water should proceed along its course in the stream bed as by its nature wont, without suffering any visible change in quantity or quality from the owners of lands adjoining the stream; moreover, it seemed logical that the private owners of these riparian lands not only might make such use of the stream as their needs required, but also might insist upon the preeminence of such uses.

But the increasing needs of the present time call for the use of water for a thousand purposes not dreamed of in the philosophy of an earlier day, and many of these modern needs have become so vital to our very life and prosperity that the public welfare now demands that they be definitely recognized and provided for. Some of these modern uses produce profound effects. upon the character of the stream. For example, for the