1837.] 



for icidenhig the Pamban Passage. 



121 



country match having failed. The divers and boatmen had not entirely 

 recovered from the effects of the festival. Removed 652 feet of stone. 



21st. Only half a day's work was done, as the weighing boat and 

 tackle required repair ; fifteen charges fired, and 597 feet of stone re- 

 moved. 



22d. The current was to-day exceedingly strong, and the divers gave 

 up early ; six charges were fired, and 350 cubic feet of stone removed. 



At day-light proceeded to examine the passage through the sand 

 bank. Its figure, as well as the soundings, do not appear to have vari- 

 ed in the slightest degree since the survey made under Major Sim. 

 The channel is precisely where it then existed, with a depth of 

 five and a half feet at the lowest tides, and about eight high water. 

 It gradually increases to twenty feet, which is found near the shore 

 close to the island of Ramisseram, and the greatest depth close to the 

 edge of the bank on its eastern side; the remainder of this space has 

 seldom more than ten and twelve feet water ; bottom, rocks mixed with 

 coarse sand, broken coral, &c. All vessels are obliged to pass over 

 this part. Those proceeding to Ceylon have an open passage, with 

 eighteen feet water; the channel to the coast of India is round the sou- 

 thern extremity of the bank, and has only twelve feet at low tides. 

 Vessels can, however, gain the open sea by the Ceylon passage, which 

 is seldom done except when commanded by Europeans- This route is 

 well sheltered by a chain of coral reefs and islands, which protect it 

 from the S. W. winds. I followed the whole extent of the bank, and 

 found in no place but the one above mentioned more than three and 

 three and a half feet. Near the eastern side, close to Tonitora, the 

 bank is only a few yards in extent. It is said an opening was forced 

 by the storm of 1814 through this point, of equal depth to the other, 

 which gradually closed up, and it is now such as I saw it in the year 

 1809. 



Having thus ascertained that no other passage existed, I returned to 

 the point before mentioned, and commenced a minute examination of 

 its composition. Contrary to the opinion I had previously formed, the 

 centre and most shallow part was composed of fine sand, mixed with 

 blue mud, and covered with marine plants, abounding with insects and 

 sea worms, which would appear to indicate that it never suffers any 

 material change, and is not, according to the reports of the masters of 

 the dhonies, covered with sand to nearly a foot in depth during the S. 

 W. monsoon. I remained on this point till the tide had commenced to 

 flow from the north, running at the rate of nearly five miles an hour 

 over the reef; here the rapidity was trifling, never exceeding one and 

 a half miles per hour, the velocity being lost in the great expanse of 

 water over which it spreads on passing the reef. 



