THE PROBLEMS OF THE DEEP SEA. 453 



Plain men may be puzzled to understand why Dr. Wyville Thom- 

 son, not being a cynic, should relegate the " Land of Promise " to the 

 bottom of the deep sea ; they may still more wonder what manner of 

 " milk and honey " the Challenger expects to find ; and their perplex- 

 ity may well rise to its maximum, when they seek to divine the man- 

 ner in which that milk and honey are to be got out of so inaccessible 

 a Canaan. I will, therefore, endeavor to give some answer to these 

 questions in an order the reverse of that in which I have stated them. 



Apart from hooks, and lines, and ordinary nets, fishermen have, 

 from time immemorial, made use of two kinds of implements for get- 

 ting at sea-creatures which live beyond tide-marks these are the 

 " dredge" and the " trawl." The dredge is used by oyster-fishermen. 

 Imagine a large bag, the mouth of which has the shape of an elon- 

 gated parallelogram, and is fastened to an iron frame of the same 

 shape, the two long sides of this rim being fashioned into scrapers. 

 Chains attach the ends of the frame to a stout rope, so that when the 

 bag is dragged along by the rope, the edge of one of the scrapers rests 

 on the ground, and scrapes whatever it touches into the bag. The 

 oyster-dredger takes one of these machines in his boat, and when he 

 has reached the oyster-bed the dredge is tossed overboard ; as soon as 

 it has sunk to the bottom, the rope is paid out sufficiently to prevent 

 it from pulling the dredge directly upward, and is then made fast 

 while the boat goes ahead. The dredge is thus dragged along and 

 scrapes oysters and other sea-animals and plants, stones, and mud into 

 the bag. When the dredger judges it to be full he hauls it up, picks 

 out the oysters, throws the rest overboard, and begins again. 



Dredging in shallow water, say ten to twenty fathoms, is an easy 

 operation enough ; but the deeper the dredger goes, the heavier must 

 be his vessel, and the stouter his tackle, while the operation of hauling 

 up becomes more and more laborious. Dredging in 150 fathoms is 

 very hard work, if it has to be carried on by manual labor ; but by 

 the use of the donkey-engine to supply power, 1 and of the contrivances 

 known as " accumulators," to diminish the risk of snapping the dredge- 

 rope by the rolling and pitching of the vessel, the dredge has been 

 worked deeper and deeper, until at last, on the 22d of July, 1869, 

 H. M. S. Porcupine being in the Bay of Biscay, Captain Calver, her 

 commander, performed the unprecedented feat of dredging in 2,435 

 fathoms, or 14,610 feet, a depth nearly equal to the height of Mont 

 Blanc. The dredge " was rapidly hauled on deck at one o'clock in 

 the morning of the 23d, after an absence of 7 hours, and a journey of 



1 The emotional side of the scientific nature has its singularities. Many persons will 

 call to mind a certain philosopher's tenderness over his watch " the little creature " 

 which was so singularly lost and found again. But Dr. Wyville Thomson surpasses the 

 owner of the watch in his loving-kindness toward a donkey-engine. " This little engine 

 was the comfort of our lives. Once or twice it was overstrained, and then we pitied the 

 willing little thing, panting like an overtaxed horse." 



