204 Mr. Waldie’s investigations connected [No. 3, 
supply of water is necessary, but also on account of the circumstance 
that in many cases the readiest way to dispose of the liquid sewerage is 
to turn it into rivers. And as it frequently happens that these rivers 
may afford the easiest or perhaps the only practicable source of supply 
of water for other towns, the pollution of their waters so produced may 
be not a little deleterious. From the enormous extent and population 
of the English metropolis, and the comparatively small size of the 
river on which it stands, the evil in that case has become palpable and 
notorious. The most eminent chemists and engineers bave been 
engaged in the examination of the subject as respects both the supply 
of water and disposal of sewerage, and the results of their enquiries 
have been published and subjected to public criticism and discussion. 
So far as I am aware, nothing has yet been published of the results 
obtained by the examination of the waters of the Military cantonments 
‘of India, nor do I know if it be intended that anything shall be. 
With respect to the Calcutta supply, as is well known, a series of 
analyses has been made, and a Report of results and conclusions drawn 
out, by the Chemical Examiner to Government, Dr. Macnamara. 
That report, no doubt from being intended for a non-professional, and 
(regarding it collectively and officially) not a professedly scientific body, 
gives only results and conclusions, omitting altogether the details 
of analyses and the specification of the methods employed. Dr. 
Macnamara’s attention seems to have been directed chiefly to the 
water of the Hooghly, to ascertain the proper point nearest to the town 
from which a supply of water of sufficient purity all the year round 
could be obtained. The examinations were made on samples from 
Cossipore, Pultah Ghat near Barrackpore, and Chinsurah. The general 
conclusion arrived at is, that the influence of the tide is little felt at 
Chinsurah at any period of the year, not much more at Pultah Ghat, 
except towards the close of the hot season in May and June when it 
is decidedly perceptible though not great, and not only decided but to 
a large amount at Cossipore during the months of March, April, May 
and June; and that the river water from its admixture with sea water 
and the sewerage of Calcutta during that time is unfit for human con- 
sumption. The organic matter is stated to be much larger in quantity 
during these months than at other periods, and also to be highly 
nitrogenized ; the quantity amounting to 6 or 7 grains or even 10 or 
