AMERICAN INSTITUTE. 231 



The next question to be asked is, whether the agricultural value 

 of the sewerage will pay the expenses of collecting and applying 

 it. I answer, unconditionally, that it will. The expenses will 

 embrace the construction of receptacles at the river end of the 

 present sewers, and they may all be connected, as was proposed 

 by myself, at the Farmers' Club, a few days since, by proper pipes, 

 with two large receiving reservoirs, one on the east and the other 

 on the Avest side of the city, and from there be driven by steam 

 machinery tlirough mains, under the Harlem and Hudson River 

 railroads, to the agricultural districts. The economy of trans- 

 mitting such matters through mains, is well understood, and the 

 cost has been estimated, by competent engineers, at five cents per 

 ton for a distcince of five miles, and to a height of two hundred 

 feet. This includes interest on capital invested, and all current 

 expenses. 



The clieapness of lifting and removal on a large scale by steam 

 power, renders the question of levels far less important than it 

 has hitherto been considered. The expense of raising forty-five 

 thousand gallons a hundred feet high, by a twenty-five horsepower 

 engine, is about eighteen pence. There appears to be some mis- 

 conception in relation to the power of pumping, and apprehensions 

 are sometimes expressed, that mixtures of common street compost 

 would clog the pipes, and could not be pumped. This is a mis- 

 take; as I have seen in potteries, tolerably thick mud, usually 

 called slip, which is composed of clay mixed with granite and 

 powdered flint, say one and a half tons of water to a ton of solid 

 matter, pumped and and distributed with great ease. 



Mr. Low remarked on the peculiar quality requisite in drain 

 tiles, that is, their porosity. 



Prof Mapes said, that he had tried a great variety of experi- 

 ments to makes the tiles porous, such as mixing chopped straw 

 with the clay, salt, &c., which would keep until burned or dis- 

 solved out. He uses drains of from two to four inches calibre, 

 and finds that when laid deep, they drain a much greater space. 

 At five feet deep, they need not be nearer together than about 

 eighty feet. It is now a fixed truth, that thorough drainage, with 

 deep tillage, saves largely in manures, the land requiring so much 

 less in quantity. 



