474 



Town Sewage. 



are about 60 tons of sewage per head per annum ; but that, as 

 the period of the experiments was drier than usual, the amount 

 probably then reached only about 55 or 56 tons. 



By reckoning the sewage at 60 tons per head per annum and 

 the ammonia at 6|^ grains per gallon, or the sewage at 56 tons, 

 and the ammonia at 7 grains, we arrive alike at 12^ lbs. of 

 ammonia per head as the contribution made annually to the 

 sewage by a mixed population. 



This was the estimate adopted in the Report of the Com- 

 mission. 



Let us now turn to the other method of computation referred 

 to, — that based upon an examination of the faeces and urine, or 

 of the food of man. 



Table III. gives a very concise summary of the information 

 we require. 



Table III. — Amount of Nitrogen reckoned as Ammonia, and estimated Value 

 of Total Constituents, in Human Voidings, per Head per Annum. 



