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THE POPULAR SCIENCE MONTHLY 



The Dbedging Winch on the Foewabd Deck op the " Albateoss." 

 (Photograph by DeLong.) 



several models of dredges, those designed by Captain Z. L. Tanner, the 

 first captain of the Albatross, and by Professor Alexander Agassiz, have 

 been used most frequently. These consist of a pair of heavy iron run- 

 ning frames at the sides of the mouth of the dredge, connected with one 

 ■cross bar ten or twelve feet long in the Tanner model, and by two such 

 bars in the Agassiz type. Lashed to this frame is a cone-shaped bag, 

 twenty or thirty feet long, made of heavy webbing, with much finer 

 meshes near the tail than near the mouth, and with a lining of fine 

 webbing in the after part of the bag, the end being closed by a lashing. 

 An extra-heavy, six-foot dredge, fitted with strong teeth on the lower 

 beam, was also built for raking over the pearl oyster beds in the southern 

 part of the archipelago, and this small dredge has also been used to 

 good advantage in collecting over other unusually rough bottoms. 



During the Philippine cruise, the largest beam-trawl ever used by 

 the Albatross was made by connecting the usual iron runners with 

 twenty-five-foot spars, and lashing to these a bag over sixty feet long. 

 This net was handled with great success on a smooth ocean floor until, 

 while dredging in Batangas Bay on Washington's Birthday, 1909, the 

 dredge caught on some obstruction and, after a moment of severe 

 tension, gave way. When the wreck was brought to the surface, it was 

 found that both of the heavy pine spars had been snapped in two, and 

 that only a few shreds of the long bag were left hanging to the remains 

 of the frame. This, indeed, is the fate of many a good, deep-sea dredge. 



Two models of nets have been used for trawling between the surface 



