PACIFIC AND BEERING'S STRAIT. 259 



filled up ; but, on the contrary, that the passages chap. 

 through the reefs were apparently always in the w-y^j 

 same condition. The only direct evidence, however, *?'i* 



J 1826. 



which I could obtain of this fact was that of the 

 Dolphin reef off Point Venus in Otaheite. This 

 reef, when first examined by Captain Wallis in 

 1769, had " two fathoms water upon it." Cook 

 sounded upon it a few years afterwards, and gave 

 its depth fifteen feet. In our visit to this place, we 

 found, upon the shallowest part of it, thirteen feet 

 and a half. These measurements, though at vari- 

 ance, from the irregularity of the surface of the 

 reef, are sufficiently exact to warrant the conclusion 

 that it has undergone no very material alteration dur- 

 ing an interval, it should be recollected, of fifty-six 

 years. But the Dolphin, as well as the above-men- 

 tioned reefs and channels, are within the influence 

 of rivers, which, in my opinion, materially retard 

 their increase, and their growth must not be taken 

 as a criterion of that of the islands of which I have 

 been speaking. With regard to them, there is one 

 fact worthy of consideration, and upon which every 

 person must form his own judgment. I allude to 

 the remains of the Matilda, a ship which a few 

 pages back is stated to have been cast away upon 

 one of these coral islands. In my description of 

 Matilda Island, it is stated, that one of the anchors 

 of this ship, a ton in weight, a four-pounder gun, 

 her boilers and iron- work, are lying upon the top of 

 the reef, two hundred yards from the present break 

 of the sea, and are dry at low water.* The nature 

 of these articles and the quantity of iron bolts and 

 other materials lying with them renders it probable 



* The rise of the tide is about two feet. 

 s 2 



