220 Mr. Waldie’s investigations connected [No. 3, 
9th December, 1865, Ebb, Surface, On Ae a0? 
Weepyane.. Tae 78 0175 
25th February, 1866 Ebb, Surface, ahh ee 92 
Deep, ... 1s Bae 45 
2nd May, Ebb at Bankshall, southern part of 
Calcutta, ie uae an ae Bsi3 0325 
Flood at Hatkolah, northern part of Calcutta,... 2.70 
30th May, Ebb, Hor rie eee 90 0238 
Flood, ae i a AGO 0275 
14th June, Ebb, ose SB bd 90 0250 
Flood, Se 2 een Be 0225 
6th June at Chandernagore, 20 miles above 
Calcutta, Ebb, Surface, ... i oH .60 .0163 
Deep, es 67 0213 
From an inspection of this table, it will be observed that the 
permanganate test exhibits the largest quantity of organic matter in 
the river water during the rainy season, and the smallest quantity 
during the cold season, the hot season giving results intermediate.* 
The same ratio is not so distinctly perceptible in the weight of the 
organic matter. Ii the water at all these seasons were at the same 
state of dilution as regards saline matter, there would be the largest 
proportion of organic matter during the rainy season and the smallest 
during the hot season. The hot season is usually associated with ideas 
of corruption and concentration of impurities, the rainy season with 
purification by the abundance of pure water from the clouds. In 
point of fact it is directly the reverse. The same thing has been 
observed in England, as will be manifest from the following quotatioa 
from Dr. Frankland’s report on the London waters. He says, “‘ This 
* It was with considerable hesitation that I left the indications given by 
the permanganate test in the table, on account of objections raised to my 
determinations of the organic matter which led to a supplementary paper read 
at the succeeding meeting of the Society. But after due consideration, they 
were allowed to remain as sufficient for the purpose required. The objections 
will be noticed as occasion calls for it, in notes or in the Supplement. 
It is to be observed also that, as reported in the Proceedings of the Society 
for October, page 1866, 1 had stated 1.4 grains per gallon as the largest amount 
of organic matter obtained. 'T'wo of the results in the table, those of 2nd and 
30th May somewhat exceed this, viz. 2.7 and 2.6 grains corresponding respective- 
ly to 1.89 and 1.82 grain per gallon. The correctness of these was doubted from 
supposed inaccuracy in the process, but this not being certain they have been 
jutroduced into the table. 380th Noy. 1866. 
