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GGT. 
ON THE CHEMICAL EXAMINATION OF ORGANIC MATTERS 
IN RIVER WATERS. By W. E. ADENEY, F.1.C., Associate 
of the Royal College of Science, Ireland; Curator in the Royal 
University of Ireland. 
[Read May 22; Received for publication May 24; Published Jury 15, 1895.] 
In the paper which I brought before the notice of the Society 
last month’ I gave the results of an extended experimental inquiry, 
which showed that the fermentation of organic substances, contain- 
ing nitrogen, or mixtures of them with ammonium compounds, 
takes place progressively in two distinct stages in the presence 
of mixed organisms natural to surface waters—aerobic conditions 
being continuously maintained throughout the mass of the fermenting 
liquid. 
It was demonstrated by those results that during the first 
stage the organic matters—nitrogenous or non-nitrogenous— 
are completely broken down, the carbon and nitrogen (if pre- 
sent) being almost entirely converted into carbon dioxide and 
ammonia, a small quantity of organic matter remaining as such, 
but in an altered form; and that, during the second stage, the 
ammonia is oxidized to nitrous or nitric acids, or both, and that 
at the same time the organic matters, formed during the first 
stage of fermentation, may be partially or completely oxidized, 
carbon dioxide and possibly nitric acid being formed; and that 
further the second stage does not commence until the conclusion 
of the first. 
1 Scientific Trans. Royal Dublin Society, vol. v. 
