96 EXI'EDITIOX OF THE "ALBATROSS," 1899-1900. 



of the "Atlas of the Pacific," issued by the German Observatory in 1896,* 

 giving the Hnes of the specific gravity baser! upon a large amount of 

 material accumulated b}^ a number of exploring expeditions down to 1893. 



The observations of the " Albatross " practically agree with Plate 5 of 

 the German Observatory Atlas, showing a gradual increase as we proceed 

 south from San Francisco to the vicinity of the Society Islands and in 

 the Paumotus, with a maximum specific gravity on the line San Francisco 

 to Tahiti. In a general way we found also a somewhat greater salinity in 

 the lao-oons, as at Rangiroa, Fakarava, Makemo, in the Paumotus, as well 

 as in the Tongas, Fiji, the lagoons of the Ellice, Gilbert, Marshall, and 

 Carolines, at Funafuti, Taritari, Jaluit, Rongelab, Wotje, Arhno, Ualan, 

 Ponapi, Truk, and Guam in the Ladrones. 



As we proceed westward from the Society Islands there is a gradual and 

 very marked diminution in the specific gravity, reaching its minimum in 

 the Fijis. Thence it again diminishes rapidly northward at the Ellice, 

 Gilbert, and reaches on that line its minimum in the southeastern Marshall 

 Islands. It rises again in the northern Marshall Islands and going west 

 from Jaluit is somewhat less along the Carolines, falling again as we go 

 north to the Ladrones, and thence to Japan, W'ith the exception of a slight 

 rise to the west off the Bonin Islands. 



The Bottom Deposits collected by the " Challcnr/er " in the Pacific. 



The chart given by Murray and Renard,^ showing in general the nature 

 of the bottom deposits of the Pacific, naturally does not give the interesting 

 details for each sounding, showing the relation of the constitution of the 

 bottom deposits to the depth. As the line run by the "Albatross" shows 

 in a remarkable manner the same correspondence which had been first 

 ob.served by Sir John Murray between the amount of carbonate of lime 

 present and the depth, I have, for purposes of comparison, collected the 

 data of the principal stations occupied by the "Challenger" in the Pacific, 

 to show how closely the later observations of the " Albatross " agree with 

 the records of the " Challenger." 



' Deutsche Soewarte, Stiller Ozean, Ein Atlas v. 31 Kartcn, Hamburg, 189G. 

 ^ Chart 1 : Deep-sea Deposits, " Challenger " Expedition, Murray and Kenard. 



