332 "ALBATROSS" TROPICAL PACIFIC EXPEDITION. 



There are also among the Carolines a number of isolated islands and islets ; 

 they appear, from the Russian surveys, similar to some of the above-named 

 islands or to such islands as Pingelap. 



Wolea Island ^ has also been surveyed by Captain Liitke. It consists 

 of two open arcs of flats on which low islands have been thrown up, the 

 lagoons in the two arcs varying in depth — the eastern from five to 

 twenty fathoms, and the western to twenty-five. The eastern lagoon 

 is entered by a passage of about three quarters of a mile in width, 

 while the western lagoon is partly closed by two indistinct patches ; 

 the ridge separating the lagoon from the sea rises to a depth of four or 

 five fathoms. 



We may note that the islands of the western part of the Carolines run 

 from southwest to northeast, having the same general trend as the southern 

 group of the Ladrones. The line of elevation of the central and eastern 

 Carolines from Kusaie to Truk runs in a general way from south of east in 

 a westerly or slightly northwesterly direction ; a number of parallel lines of 

 elevation pass through the low atolls of the eastern and central part of the 

 central Carolines. 



The soundings made by the "Albatross" from Jaluit to Namonuito^ 

 indicate that there is no great plateau from which the Carolines rise, but 

 that the various groups are, as is the case with the neighboring groups 

 of the Marshalls and Gilberts, isolated peaks with steep slopes rising from 

 a depth of over 2000 fathoms. The line we ran from the northern end of 

 Namonuito to Guam developed the eastern extension of a deep trough 

 running south of the Ladrones. The existence of this trough had been 

 indicated by a sounding of 4475 fathoms made by the "Challenger"^ to 

 the southwest of Guam. We obtained, about 100 miles southeast of Guam, 

 a depth of 4813 fathoms, a depth surpassed only, if I am not in error, by 

 three soundings made by the " Penguin " in the deep trough extending 

 from Tonga to the Kermadecs,* and by two still deeper made by the 



1 A. Chart*772. 



2 Mem. M. C. Z., Vol. XXVI., No. 1, 1902, Prelim. Report, p. 63. Stations 238-244. 



" A. Ciiart 2935, Oceanic Soundings, Sheet 3. Named "Challenger Deep" in the Summary of 

 Results, Chart Ic, of the Voyage of the " Challenger." 

 < Ibid. 



