14. THE DEPTH AND MARINE DEPOSITS OF THE PACIFIC OCEAN. 
. and as we approach Guam, .. . in 2337 fathoms, we come upon de- 
posits of fine volcanic sand. 
“No soundings were made by the ‘ Albatross’ on the line from Guam to 
Yokohama, as the line is parallel for a considerable length with that run by 
the “Challenger’ from the Admiralty Islands to Japan.” 
The same report also includes a few remarks by Sir John Murray on the 
bottom deposits,' accompanied by two colored maps: one showing the dis- 
tribution of the deposit types, and the other showing the depths, in the por- 
tion of the Pacific traversed by the “ Albatross.” 
Fourth Expedition. —In the winter of 1904-1905 Dr. Alexander Agassiz 
made his most recent expedition in the “ Albatross” in the eastern tropical 
Pacific. From San Francisco the “ Albatross” proceeded to Panama, thence 
to the Galapagos Islands, and to Aguja Point in Peru, thence out into deep 
water and to Callao in Peru, thence to Sala y Gomez and Easter Island, then 
back to Galapagos Islands, thence to Manga Reva in the Paumotu Archi- 
pelago, and finally from Manga Reva to Acapulco. The following remarks 
on the bottom-deposits are extracted from Dr. Agassiz’s General Report of 
the Expedition :” 
“ Off Mariato Point [on the voyage from San Francisco to Panama] the 
‘ Albatross’ made two hauls in the vicinity of the stations where in 1891 she 
found ‘modern greensand’ in 555 and 782 fathoms. It was interesting to 
find the greensand again, as the specimens collected in 1891 were lost in 
transit to Washington. . . . On the 2d [November] we left [Panama] for 
Mariato Point to make a few additional trawl hauls in the region of the 
greensand. In both the hauls made off Mariato Point greensand was 
found, but not in the quantity obtained in 189]... . 
“The bottom of the area explored by the ‘ Albatross’ in 1891 is covered 
by green and brown mud mixed with masses of decayed and decaying vege- 
table matter. South of this area we come upon the great tracts of the 
Eastern Pacific, the bottom of which is covered by manganese nodules. 
The extent of this tract is shown in Plate 3, where are given the northern 
and eastern limits of the manganese nodules as well as its southern limit 
extending from Easter Island to Manga Reva. From the northern extrem- 
ity of Moser Basin the line forming the northern limit of the manganese 
1 Mem. Mus. Comp, Zodl., Vol. XXVI., 1902, pp. 109-111, maps 1* and 1. 
2 Ibid., Vol. XXXTII., 1906, pp. xi., xii., 5 et seq. 
