16 University of California Publications in Zoology [ Vou. 14 
made the apparatus finally adopted, and himself contributed a number 
of its distinguishing features. f 
This instrument avoids the two principal defects of the Ekman 
apparatus: (1) the undue raising of the center of gravity, owing to 
the concentration of weight at an elevated point, and (2) the insuffi- 
cient mechanism for closing the lower end of the tube, after the 
entrance of the bottom material. The former result is attained by 
distributing the weight uniformly from a level not far above that of 
the lower end of the tube for a distance of 4 feet 6 inches (137 em.) 
along the latter. The shutting in of the tube contents at the lower 
end is insured by a special valve whose structure and mode of oper- 
ation will be deseribed shortly. Many of the features of our appar- 
atus have obviously been borrowed from that of Ekman. 
This improved instrument has been named the ‘‘ ‘ Albatross’ 
> 
30ttom-sampling Apparatus.’’ The chief features of its construction 
are shown in plates 12 and 13. Two examples, differing slightly in 
construction, have been manufactured for the use of the ‘* Albatross’’. 
The first of these, after being used very successfully in San Francisco 
Bay, was sent to the Fisheries steamer ‘‘ Fish Hawk,’’ for use in the 
Gulf of Mexico. The second differs from this chiefly in the length 
of the upper rod or stem (Stm), which is shorter and thicker in the 
later pattern. This change was made owing to the tendency of this 
rod to bend under the influence of the powerful lateral strain to which 
it was frequently subjected in being hauled out of the mud. 
The length of the second model is 9 feet 3 inches over all (282 em.), 
that of the first one being somewhat greater than this. The length 
of the inner tube, between the upper and lower valves (and thus the 
maximum length of the samples taken), is slightly less than 6 feet 
(180 em.). The total weight of the apparatus is 154 pounds (70 kilo- 
erams) for the first model, or 175 pounds (79.5 kilograms) for the 
second. With the exception of the lead filling, the instrument is 
constructed wholly of brass and bronze. 
The Albatross sampling apparatus is divisible at the flanges (F1.) 
into two leneths, which are uncoupled by loosening the wing-nuts. 
+The application of this particular type of valve is Mr. Arntzen’s chief 
contribution to the instrument, and upon it, in large measure, depends the 
success of the latter. His originality in this invention is in no wise lessened by 
the faet that a somewhat similar arrangement had already been employed by 
the Prince of Monaco, since this fact was overlooked until the completion of 
our own instrument. (See Richard, 1900, pp. 13 to 16, figs. 8, 4, 5.) The valve 
there deseribed is only roughly comparable with our own, however, and other- 
wise the two instruments have little in common. 
