HARD WICKE 'S S CIENCE -GOSS IP. 



i33 



may be detected. If the dredge is jerking and 

 bounding, the boat is being pulled too fast, whereas, 

 on the other hand, too slow a progress causes the 

 irons to sink too deeply ; but when all is as it should 

 be, the hand feels a gentle quivering, which proves 

 the machine is working steadily. Do not, how- 

 ever, hold the rope too tightly, else, in the event 

 of the dredge being suddenly anchored by a stone, 

 you, in all probability, will collide rather unpleasantly 

 with the side of the boat. Should the dredge get 

 entangled, the best way to free it is to retrace 

 ground, and, in most cases, it will free itself on being 



place in the tray. The process of sifting is greatly 

 facilitated by washing the top mass. 



My first day's dredging off Rossbeigh was about a 

 mile from shore. This attempt was made from a. 

 native canoe, and from the little hold the craft had 

 upon the water, the dredge could scarcely be got to 

 work. The only benefit that accrued to me from 

 that day's work was a rough knowledge of the depth 

 of the water and the nature of sea-bottom, which, 

 unfortunately, largely consisted of heavy, rounded 

 stones. The next day's work was undertaken at low 

 tide. The course chosen was further out to sea ; but 



Fi:j. 99. NymJ>ho)i gracilis. 



towed in an opposite direction ; if that means fails, 

 the rope must be strained until the spun yarn, already 

 alluded to, breaks, when the dredge, being capsized, 

 will easily free itself. 



Supposing all to have gone on well, after half an 

 hour the dredge may be lifted rapidly, but steadily, 

 to the surface, taking care to lift it clear of the side of 

 the boat, else you run the danger of crushing the 

 Crustacea and shells it may contain, and the contents 

 emptied into sieve No. I (the coarsest). Large 

 shells, stones, &c, are here retained, the smaller 

 specimens successively passing into sieves Nos. 2 and 

 3, and finally the very minute forms find a resting- 



even at this distance from land (about 1 h mile from 

 shore), where comparatively deep water might have 

 been expected, the depth did not, I should judge, 

 exceed 5 to 7 fathoms, the dredge coming up choked 

 with Rhodosferms and other sea-weeds, mostly 

 Polysiphonia and Ptilota. However, on emptying 

 the dredge, a variety of marine animals were dis- 

 covered, which, although not rare, were none the 

 less curious. Two specimens of Pisa tctraodon 

 rather obtrusively first made their appearance, and, 

 were followed soon by what very easily might have 

 been mistaken for a lump of sea-weed, Stenorhyiichits 

 phalangium ; several specimens of the Hermit Crab- 



