78 
Proceedings of the Royal Society 
very marked on the countenance of the Prime Minister of Cochin, 
who had ventured on the sea, probably for the first time. In 
return for the compliment, he turned out the state snake-boats of 
the Rajah to attend us next day. They are very long narrow- 
framed canoes, each with some fifty rowers, who sit with their legs 
dangling over each side of the boat alternately ; and they go at a 
great pace. The “ bucksheesh ” for so many men came to be 
heavy ! 
I sent a diver down for a specimen of the mud (which I regret 
to have lost). It is of a peculiarly greasy nature, dark green in 
colour, and sticky ; a specimen was analysed at Madras in 1861, 
and was found to contain — 
1. Very minute angular fragments of quartz, the largest hardly 
visible without a lens ; this is the sand 
2. Foraminiferous shells of the genus Rotalia, and a few frag- 
ments of larger shells. 
3. Upwards of twenty genera of Diatomacem. 
4. A few specules of sponges and corals, very minute. 
5. Some amorphous matter, which was not destroyed after long 
boiling in strong acids. 
I reported to the Government against attempting to open out 
communication between either of the mud hanks and the adjoining 
backwater. A cut through the neck of land between would throw 
an outwards scour during ebb tides, and during the rains into the 
centre of the mud hanks, and might do a great deal of harm, and 
indeed destroy them, or shift their position. During the dry 
season, at flood tide the mud would be drawn into the backwaters, 
and choke them up. 
If a lock were to be put on the canal, the channel leading to it 
could not be kept clean without a scour. 
At Narrakal there is already a canal from the backwater to 
within a few yards of the shore ; and at Allippey there is a similar 
one, only the mud bank has left it and travelled south. 
These natural harbours of refuge are too valuable to try ex- 
periments on ; and I think the whole phenomena connected with 
them are well worthy of car ej ul scientific investigation. 
