and Laboratory Methods. 



1233 



LETTING DOWN THE DREDGE. 



the drum was reeled something over three hundred fathoms of cast steel rope, 

 not a foot of which was lost during the entire trip. 



Of course the reeling in of this rope with a heavy dredge at its end under the 

 direct heat of the tropical sun was no child's play, and taxed the endurance of 

 even the most enthusiastic. But it was 

 done, and to good purpose. Incidentally, 

 it may be remarked that in my opinion 

 this work had a good deal to do with the 

 excellent physical condition of the men 

 during the cruise. 



Dredges of the regular " Blake " pat- 

 tern were used. These and the trawls, 

 also practically like those used on the 

 Blake, were made in the engineering de- 

 partment of the university at surprisingly 

 small expense. Trawls, however, are of 

 little use where the bottom is rocky, as 

 was the case almost everywhere in that 



region at a depth of from fifty to two hundred and fifty fathoms. By far the 

 most effective instrument, and the one upon which we eventually depended almost 

 exclusively, was the tangles, made after a pattern suggested by Dr. James E. 

 Benedict of the National Museum. This proved such a decided success that I 

 may be excused for giving its construction in detail. A four-foot length of 1x2- 

 inch iron bar is bent in the middle at nearly a right angle. Five iron rings 

 are bolted at regular intervals to the inner side of this bar, and to each ring 

 is fastened a two-foot length of fairly heavy chain. Through each link of 

 these chains is passed a six-foot strand of 2^ -inch Italian hemp rope, each 

 strand being tied in the middle and thoroughly unraveled throughout its length. 



The dredging cable is attached to a hook 

 bolted to the outer side of the angle of the 

 bar. The amount of material secured by 

 this device was astonishing, and included 

 all sorts of things from corals to fishes, 

 quite a number of the latter being secured 

 in this way. 



Being provided with several of these 

 tangles, we were able to economize time 

 by detaching one from the cable as soon 

 as it came up, and sending another down 

 to be at work while we were picking over 

 the first one. Many hands made this 

 usually irksome labor light. Each student had a particular group of marine 

 animals to look after, and he was responsible for the care of all of the material 

 in his group, and had prepared himself to do just that work. The result was that 

 the collections as a whole came through in very good shape. 



We were astonished to find the amount of knowledge of the various groups 



DREDGING ON POURTALES PLATEAU. 



