[79] IT. f?. PISH OOMMISS^WN feTEAMER ALBATROSS. 81 



Tbe washers are 6| inelies in rtiauieter, tliree-sixt(^eiitlis inch thick, 

 aud have a hole in the center if^ inches in diameter. A luib one-halt' 

 inch in length extends from each side of the washers (Figs. 5 and G), ex- 

 cept those in contact with the yoke and cross-heads, which have no hub 

 on that side. The buffers were purchased of the New York Kubber 

 Belting Company, and are composed of their comi»ound No. 23. Tliey 

 are 5^ inches in diameter, 3 inches thick, have a hole 1^^ inches in di- 

 ameter through their center, weigh 4 pounds Bounces, and cost G7 cents 

 per pound, or about $2.80 each. 



A scale not shown in the plate is lashed to one of the guide rods, and 

 marked to indicate the strain on the dredge rope to each 500 pounds by 

 compression of the buffers. 



The accumulator is useful, not only to relieve sudden strains brought 

 upon the dredge rope by the vessel's motion in a sea way, but it insures 

 a more uniform action of the hoisting engine, and gives the first indica- 

 tion of increased tension on the rope in case the trawl fouls or buries in 

 the soft bottom when working in deep water. 



The hubs on the brass washers, which prevent the buffers from com- 

 ing in contact with the tension rod, w^ere devised by Lieutenant-Com- 

 mander Sigsbee, U. S. N., on board of the United States Coast Survey 

 steamer Blake. Previous to their introduction the buffers were liable 

 to grip the tension rod while they were compressed, making the appa- 

 ratus sluggish in its action, a fault that no longer exists. It is, on the 

 contrary, exceedingly prompt in expansion after being relieved of its 

 load, and retains its elasticity under all conditions of service and tem- 

 perature. 



THE DREDGE ROPE. 



Our rope is made of galvanized steel wire, and was manufactured by 

 the Hazard Manufacturing Company, Wilkesbarre, Pa., C. M. Thomp- 

 son, agent, 87 Liberty street. New York. It is three-eighths inch in di- 

 ameter and has six strands, laid around a tarred hemp heart. The 

 strands are composed of seven wires, each made according to a special 

 gauge of the manufacturers, approximating to No. 18 American or No. 

 19 Birmingham gauge. It weighs 1.32 pounds i>er fathom in air, about 

 -1.2 pounds in water, and its ultimate strength determined by the test- 

 ing machine at the ordnance department, navy-yard, Washington, D. 

 'C, is 12,850 pounds. A kink reduces the strength about 50 per cent. 



We first received 4,000 fathoms in one length wound on a heavy 

 wooden reel, from which it was transferred to the working reel. The 

 ;spare rope was supplied in lengths of 1,000 fathoms, each length w^ound 

 >on a wooden reel. Subsequently the rope was ordered in 500 fathom 

 lengths, the reels being much more convenient for stowage'and lighter 

 to liandle. 



When transferring this rope from one reel to another or when it is in 

 use Ibr trawling or dredging, it is al)soIutely necessary to keep it under 

 tension, for if slacked from any cause it will kink, continuing to do so 

 H. Mis. G7 



