1866. ] with the supply of water to Calcutta, 227 
carefully examining wherein they lie, in order to see if they can be 
avoided. Yet notwithstanding these inaccuracies, it seems to me 
that the general results are pretty evident, that the amount of 
“ammonia is greatest in the rainy season, diminishes during the cold 
one, and again increases during the hot, which increase, however, is 
probably not in the river water proper. One examination of water 
from Chandernagore, which was very slightly if at all contaminated 
with tidal water, yielded only .0118 grain ammonia in 100,000 flood 
grains. This conclusion is not a certain one; to make it so, it would 
be necessary to have examinations of the Chandernagore water at all 
seasons; but other considerations, to be afterwards noticed, render it 
probable.* 
I am disposed to attach a good deal of importance to the estimation 
of the ammonia, not only because it helps to indicate how far the 
nitrogenous matter has gone in the stage of decomposition, but because 
that stage is not improbably one of importance. It has been long 
known that many, I may say most, of the organic proximate principles 
found in vegetables are alkaloids possessing active properties and 
producing the most marked physiological effects, and that there are 
many similar principles produced in the decomposition of nitrogenised 
substances by destructive distillation or otherwise, which possess marked 
physical properties, and probably, if they were examined, also decided 
physiological actions. But by modern chemical research, it would 
appear that these alkaloids are all formed on the type of ammonia, 
or are ammonias having one or more atoms of its hydrogen replaced 
by some other organic combination or radical. Hence it seems not at 
all unlikely that such compound ammonias as they are called may be 
produced at the same time and along with the ultimate or ordinary 
ammonia. And even though no such compounds should exist, the 
amount of ammonia would give some probable indication of the stage 
of decomposition, and existence of compounds is a state of transition 
towards ammonia, 
* The examinations for ammonia were all made about the same time in the 
month of August, consequently the waters were of different ages. The samples 
had been preserved mixed with a little Hydrochloric acid and mostly in a 
concentrated state. Of course objections may be made to their value on this 
account and possibly may be valid, This will again be referred to in the sequel, 
30th November, 1866, 
