180 



REPORT 1871. 



The amount of ammonia in the effluent water is too high, amounting to 

 more than one seventh of that in the same volume of sewage, while albu- 

 minoid ammonia still remains to the extent of one fifth of the original amount ; 

 and the almost total absence of nitrates and nitrites in the effluent water 

 shows the want of conditions favourable to oxidation ; so that the jjurification 

 of the sewage here, although considerable, is not so satisfactory as could be 

 wished, or as might be effected by making filtration through the soil an essen- 

 tial feature in the process. 



South Farm. — In 100,000 parts. Samples taken in the proportion of -^^^ 

 part of the flow per minute, by a measure graduated to yiy of a gallon. 



The results attained on the southern farm are, as shown by the above ana- 

 lyses, very unsatisfactory, and at the same time very reliable, as the slight 

 diminution of the chlorine in the effluent water would lead us to believe that 

 the loss of water due to evaporation had been about balanced by the influx 

 of underdrainage water, so that no great amount, at any rate, of concentra- 

 tion had taken place. 



We notice at once the large amount of " actual " and of " albuminoid " 

 ammonia Avhich escapes unoxidized in the effluent water. jVo less than four 

 ninths of the " actual " ammonia and more than one third of the " albu- 

 minoid " ammonia, in the same volume of sewage, escapes in the effluent 

 water, while the amount of nitrates and nitrites is very small ; the effluent 

 water is very impure indeed. 



The analyses show distinctly that at these two farms, as at present man- 



