[47] FISHERIES OF THE UNITED STATES. 559 



Plate 39. Detailed plans of Sigbee's detacher used in connection with 

 a modification of Captain Belknap's sounding cylinder No. 2. 



Plate 40. Detailed plans of Sigsbee's water specimen cup. 



Plate 41. Sounding with wire; curve for correcting the reading of the 

 register placed on the axle of the sounding reel, by Lieutenant-Com- 

 mander Sigsbee, United States Navy ; Commander Howell's method 

 of splicing the wire; Lieut. Commander Sigsbee's method of splicing 

 the wire into the " stray line." 



Plate 42. Sigsbee machine for sounding with wire ; pattern of 1881. 

 Fig. 1, rigged for reeling in by steam. Fig. 2, in temporary dis- 

 use. 



Plate 43. Sigsbee machine for sounding with wire; pattern of 1881. 

 Fig. 1, rigged for paying out; clamps in use. Fig. 2, folded for 

 transportation or stowage. 



APPARATUS FOR COLLECTING ZOOLOGICAL MATERIALS. 



Naturalists' Deep-Sea Dredge, for use from a large vessel or steamer. 



United States Fish Commission. 

 The naturalists' dredge ordinarily employed on the American coast 

 for all kinds of bottom, excepting those of soft mud and ooze, is of the 

 old pattern, long since adopted both in Europe and the United States. 

 For use from large vessels it is constructed of the following dimensions: 

 The frame measures 2 feet long, and about 5£ inches broad inside, at 

 the hinder end. The upper and lower sides, or scrapers, are 2f inches 

 wide, and one-half inch thick posteriorly, but thin out to a sharp edge 

 in front, and flare considerably, so that the width of the mouth between 

 the scraping edges is about 7£ inches. The end pieces are of three- 

 quarter-inch round iron, welded to the scrapers. The handles are 18 

 inches long, of three-quarter-inch round iron. Two different styles of 

 nets are employed with this size of dredge frame, both woven of twine, 

 one being closed at the hinder end, and the other open to permit of the 

 contents being emptied without reversing the net. The latter form, which 

 has given the greatest satisfaction, is made about 3 feet long, of web- 

 bing, having three or four meshes to the linear inch, and is securely 

 tied at the hinder end before lowering. Either kind of net is covered 

 with a bottomless bag of heavy canvas, about 3J feet long, and attached 

 directly to the frame. It is intended to protect the net against wear. 



Naturalists' Boat-Dredge, for use from a small sail-boat, row-boat, or steam- 

 launch. 



United States Fish Commission. 



The so-called boat-dredge differs from the deep-sea dredge merely in 

 size. It is intended for use from a sail boat or steam-launch. The frame 

 is 18 inches long, 5£ inches wide inside, and 7 J inches wide between the 

 scraping edges. The scrapers are one-half inch thick and 2£ inches 

 wide; the handles are 16 inches long, and the net is 2^ feet long, with 



