164 
ANALYSIS OF THE WATER. 
detect sulphuretted hydrogen, and did not find it to be 
in the least discoloured by thena. After having been 
exposed two days to the atmosphere, it was quite clear, 
but then began to smeU of sulphuretted hydrogen, 
which he discovered by the above-mentioned agency. 
After having been kept a greater length of time the 
odour ceased, the taste was good, and there was no 
indication of this gas. 
The water at low tide was nearly pure, but with a 
slightly saline taste, and we only found in it a small 
quantity of the muriate of magnesia, combined with 
calcareous matter. The sediment obtained from one 
pint and a half of the river-water, weighed forty-one 
gi'ains when dry, and was at first blue — like the clay in 
the bed of the river — with a film of red colour. On 
being disturbed, the whole became reddish; the first 
weighed thirty-five grains, the last only six, and con- 
sisted chiefly of oxide of iron. By a rough analysis it 
was found to contain oxide of iron, carbonate of iron, 
oxide of manganese, with a large portion of vegetable 
matter. 
We took in water for the ship’s consumption along- 
side and filtered it, after treating it with a solution of 
chloride of lime. 
The temperature of the fresh-water was lower than 
that of the sea : on leaving the anchorage outside the 
bar, we found it gradually decrease as we got within the 
river ; but we had not sufficient time and opportunity 
to be able to determine, by frequent and simultaneous 
