SECRETARY'S REPORT. 279 



or 26 feet of movable pipe of 2| inches bore, was about two 

 dollars, which is about double the price of the fixed tubes of 

 the same size. It is so easily laid, and the joints so well fitted 

 that a 4| inch bore might be used instead of the smaller size 

 which would discharge a stream equal to that at the point of 

 suction. 



The night-soil is taken from the cesspools with which each 

 house is usually furnished, and which are emptied in the night 

 once or twice a year by carts to which is attached a pumping 

 apparatus which fits into an opening connected with the pits. 

 The carts then carry the soil to a great sink just outside the 

 city, from which it is forced by steam pumps to a great reser- 

 voir at Bondy, where it is partly dried and made into poudrette, 

 or carried on by canal-boats to the farm at Vaujours. 



Analysis shows that the night-soil of Paris contains about 

 7f lbs. of nitrogen, equal to 9i lbs. of ammonia, to the cubic 

 metre, or cubic yard, which is a ton. It does not contain all 

 the wash of the streets and the aqueducts, like the sewers of 

 London, where an average ton contains only about 3^ ounces 

 of ammonia and 2 ounces of mineral matter. The vidange of 

 Paris contains forty times as much ammonia per ton as the 

 sewage of London, according to Prof. Voelcker. 



The most economical mode of application was also to be 

 tested. The barrel, either with or without the means for the 

 even distribution of the fluid, has been in use in Belgium, in 

 Northern France, and some parts of Germany and Switzerland, 

 from time immemorial. It has the advantage of simplicity of 

 construction and small outlay of original capital, but in the 

 end, Prof. Moll says, it is neither simple nor economical. 



" It has been my fortune," he continues, " to employ, under 

 the same circumstances, the tubular system in its integrity ; 

 that same system, both aided by gravitation and in connection 

 with the water-cart, and lastly, the cart filled by hand and 

 emptied either by direct action or the use of the tub and scoop. 

 The estimates I shall give are based on extensive trials, if not 

 on constant practice. 



"A few preliminary remai4:s are desirable. When liquid 

 manure is applied to growing crops, it must be much diluted 

 with water. If it is urine, with three or four times its bulk ; 

 if night-soil, with five or six times as much water, and then 



