148 



SOUNDINGS BETWEEN THE GROUPS. 



a lucrativG trade might be carried on by the 

 people of Swan River with the Mauritius ; for the 

 lake on the island of Rottenest affording a large 

 supply of salt, any quantity of fish might easily be 

 caught and cured. The whole group is abundantly 

 supplied, though no where so plentifully as at 

 Snapper Bank. 



From near the south-east end of this bank the 

 main w^as visible from the Beagle's poop. Here we 

 anchored for the night in 24 fathoms, and next 

 morning stood out to sea between Easter and Pelsart 

 Groups to ascertain if there were any more reefs 

 to the westward, though the long unbroken swell 

 was almost sufficient to convince us that there were 

 none. In a line between the outer reefs of 

 the two groups the depth was 36 fathoms; a mile 

 and a half further in we had 29 ; but outside 

 it 'deepened off suddenly to no bottom with 70, 

 and in two miles and a half to none with I7O. 

 Before returning we tried for bottom with 250 ; 

 but, as has been already mentioned, without suc- 

 cess. Outside the reef we felt a current setting 

 a mile an hour N. N. W. In standing- in again 

 we passed close round the north-west end of the 

 reef encircling Pelsart Group, in 31 fathoms, and 

 anchored in I7, just without a line of discoloured 

 water, which we found to have 5 fathoms in the 

 outer part, extending across the mouth of the 

 lagoon ; the largest island bearing S. by W. one 

 mile and three-quarters. 



