558 FISHEEIES OF THE UNITED STATES. [46] 



Plate 17. Another view of the same. 



Plate 18. Plan of patent trunk reeling- engine for the Sigsbee sound- 

 ing-machine to occupy the place on the bed board at present 

 assigned to the strain-pulley, should the latter not be required. 

 Designed by Mr. Barle 0. Bacon. 



Plate 19. Water- specimen cup for getting a single specimen at each 

 haul; independent poppet-valves. Used in the Coast Survey for a 

 number of years. 



Plate 20. The Sigsbee water- specimen cup for getting specimens from 

 various depths at a single haul, by using a separate cup for each 

 depth from which a specimen is required. The construction is 

 shown on plate 40. 



Plate 21. Fig. 1, case for the Negretti and Zambra deep-sea ther- 

 mometer. Fig. 2, the Negretti and Zambra deep-sea thermometer 

 without its case. Fig. 3, The Miller-Casella deep-sea thermometer, 

 apart from its case. 



Plate 22. Same as above. 



Plate 23. The Negretti and Zambra deep sea thermometers in use. 



Plate 24. The Blake, at the Washington navy-yard. The dredging- 

 gear ready for work. 



Plate 25. Fig. 1, style of dredge supplied for the first dredging expedi- 

 tion of the Blake. Figs. 2, 3, 4, dredge devised by Lieut. Com- 

 mander C. D. Sigsbee, United States Navy, and Master H. M. 

 Jacoby, United States Navy, and adopted for use. 



Plate 26. Fig. 1, plan of trawl as first used on board the Blake. Fig. 

 2, plan of trawl as improved by Prof. A. Agassiz, Lieut. Commander 

 Sigsbee, and Lieutenant Ackley. 



Plate 27. The improved trawl ready for use. 



Plate 28. The improved trawl shown as having "tripped," after foul- 

 ing with rough bottom. 



Plate 29. Plans of the deck and apparatus of the Blake. 



Plate 30. View of the Blake's deck, looking forward from the bow of 

 the starboard-quarter boat, ready for paying out the dredge. 



Plate 31. View of the Blake's deck, looking aft from the starboard 

 side of the pilot-house, ready for dredging. 



Plate 32. The forward side of the dredge-reel and its engine ; the reel 

 has 2,700 fathoms of the wire dredge-rope. 



Plate 33. View of the main hoisting engine from the starboard side. 



Plate 34. Figs. 1 and 2, iron snatch-block for dredge-rope. Fig. 3, 

 improved accumulator for dredging. 



Plate 35. The plotting of a line of soundings. 



Plate 36. Detailed plans of an improved machine for sounding with 

 wire, on the principle of Sir William Thomson, by Lieut. Commander 

 C. D. Sigsbee, United States Navy. 



Plate 37. Continuation of plate 36. 



PLATE 3S. Continuation of plates 36 and 37. 



