CHAP, VI.] DEEP-SEA DREDGING. 290 
of very characteristic pale grey Atlantic ooze. The 
total weight brought up by the engine was— 
2,000 fathoms, 24-inch rope . .. . . . 4,000 lbs. 
WOOO tathoms, Zanch;rope. ..°. = « = « L,d00 RR, 
5,500 Ibs. 
Weight of rope reduced to one-fourth im water = 1,375 Ibs. 
Dredge and bag a i ea cee Veoh au PAD ey 
Wozembrouchtupe to G25 ee 7 ee es 1685, 
Wwieichtrattached, ©) 92 "sistant Se et me pos 224 4, 
2,042 lbs. 
Much more experience will yet be necessary before 
we can assure ourselves that we have devised the 
dredge of the best form and weight for work in the 
deep sea. I rather think that the dredges, 150 to 
225 lbs., which we have been in the habit of using, 
are too heavy. In many instances we have had 
evidence that the dredge, instead of falling gently 
upon the surface and then gliding along and gather- 
ing the loose things in its path, has fallen upon its 
mouth and dug into the tenacious mud, thereby 
clogging itself, so as to admit but little more. I 
mean to try the experiment of heavier weights and 
lighter dredge-frames in the ‘Challenger,’ and I 
believe it will be an improvement. 
In many of our dredgings at all depths we found 
that, while few objects of interest were brought up 
within the dredge, many echinoderms, corals, and 
sponges came to the surface sticking to the outside 
of the dredge-bag, and even to the first few fathoms 
of the dredge-rope. 
This suggested many expedients, and finally 
