3QO 



NA TURE 



\Jan. 27, 1 88 1 



DEEP-SEA EXPLORATION^ 



THIS subject is one in which I have for many years taken 

 much interest ; and I will give you the result of my experi- 

 ence and studies. It is highly fascinating to all persons of 

 ordinary intelligence, although they may not be naturalists. 

 Gur best poets have not disdained to sing its praises ; one of 

 them says, 



" There is a magnet-like attraction in 

 These waters to the imaginative power 

 That links the viewless with the visible, 

 And pictures things unseen." 



Speculations of this kind were not unknown to the ancients. 

 In the "Haleutica" of Oppian, written nearly seventeen 

 centuries ago, it is stated that no one had found the bottom of 

 the sea, and that the greatest depth ascertained by man was 300 

 fathoms, where Amphitrite had been seen. But this grand d,s- 

 covery does not seem to have satisfied the poetical philosopher ; 

 and he enters into a long disquisition as to the many other 

 wonderful things that may be concealed in the recesses of the 

 bjundle,-,s ocean, adding, nevertheless, what I will translate from 

 the Greek : — 



" But men have little sense and strength." 

 However, man has not degenerated in this kind of knj-.\ledge 

 since the days of Oppian ; for he has now not only explored the 

 greatest depths of the sea, but has mapped out its main features 

 with nearly as much accuracy as he has done with respect to the 

 land. 



It will be more convenient to divide the subject into separate 

 heads, viz. :— (i) Historical; (2) Apparatus; (3) Fauna; (4) 

 Food ; (5) Light ; (6) Temperature ; (7) Depth ; (8) Inequalities 

 of the Sea-bottom; (9) Deposits; (10) Geological; (11) Inci- 

 dental; (12) Concluding Remarks. 



I hope you will not be frightened at the number of these 

 heads. Some of them you will find to be exceedingly short. 



1. Historical. — Sir Wyville Thomson's " Depths of the Sea" 

 gives an excellent account of the origin and progress of deei^sea 

 exploration up to a very recent perirjd. To this work I ^^ ouM 

 refer my audience, cjnteiiting myself with some supplemental 

 remarks. 



In 186S commenced the systematic examination of the sea-bed 

 at considerable depths in that part of the North Atlantic which 

 surrounds the British Isles. 1 then took my yacht, the Osprcy, 

 for another excur>ion to Shetland, and dredged ofl" the most 

 northern point of our isles. The greatest depth which I attained 

 was 170 fathoms, or 1020 feet, each fathom being 6 feet. Tliis 

 depth, strictly speakin^^j, is beyond the lin; of soundings, viz. ico 

 fathoms : and it may be a question whether the fauna of the 

 sea-bed outside of that limit can be regirded as British, although 

 adjacent to our coasts. If it be we ought to take the "medium 

 filum aquae " (as the lawyers in the time of Coke called it), and 

 extend the geographical limit of the British marine fauna half- 

 way across to North America! But such bound tries are neither 

 national nor rational. We cannot lay claim to so extensive a 

 dominion. International boun'laries, for the purpose of nival 

 warfare or as defined by fishery treaties, are liaiited to a distance 

 of three miles, irrespective of depth. Later in the same year 

 (186S) Dr. Carpenter and Prof. Wyville Thomson explore!, in 

 H.M. surveying- vessel Z/_o-/z('«/«o-, the sea-bed lying betw een the 

 Butt of Lewis and the Faroe Isles, and reached the depth of 550 

 fathoms. These tentative excursions showed that the sea-bed 

 everywhere was full of life, not merely of a microscopic and 

 uiiform kind, and of a low decree cf organisation, but of a con- 

 siderable size, great variety, and a high degree of organisation. 

 In the following year (1S69) our Government placed a better 

 vessel at the disposal of the Royal Society ; and I undertook the 

 first scientific cruise in H.M. surveying-ship Porcupine. Thi,, 

 cruise was off the western coast of Ireland, and the greate-.t depth 

 dredged was 1476 fathoms. The second cruise was undertaken 

 by I'rof. Wyville Thomson, and extended from the south of 

 Ireland to what is probably the deepest part of the North Atlantic 

 in the European seas. Tlie greatest depth dredged by him was 

 2435 fathoms, or nearly three miles. The third cruise, under 

 the charge of Dr. Carpenter, was in the same direction as the 

 Lightning expedition, but embraced a larger a'"ea, including the 

 Shetland Isles ; the greatest depth w. s 867 fathoms. In the 

 following year (1870) the Porcupine was again placed at the 

 disposal of the Royal Society for further exploration. This 

 e.'cpeJition was divided into two cruies. North Atlantic and 

 ' A Lecture by J. Gwyn Jeffreys, LL.D., F.R.S. 



Mediterranean. The former was assigned to me, and com- 

 prised the sea-bed lying between Falmouth and the Straits of 

 Gibraltar, along the western coasts of Spain and Portugal. 

 There were 38 dredging and sounding stations, at depths 

 ranging from 81 to 1095 fathoms. The Mediterranean cruise 

 was made by Dr. Caipenter, and extended round Sicily. There 

 were 29 stations, at depths ranging from 51 to 1743 fathoms. 

 Prof. Wyville Thomson was unfortunately prevented by illness 

 from taking part in this year's expedition. In all these cruises 

 an abundance as well as a great variety of marine life occurred 

 at every depth. 



The Lightning and Porcupine expeditions calminited in the 

 celebrated voyage of H.M.S. Challenger round the world, 

 which commenced on December 21, 1872, and ended on May 

 24, 1S76, having thus occupied a period of three years and five 

 months. During this expedition about 30,000 nautical miles 

 were traversed, 504 soundings were taken, and 132 dredgings 

 and 150 trawlings were made. The depths of soundings were 

 from 25 to 4475, of dredgings from 4 to 3S75, and of trawlings 

 from 10 to 3050 fathoms. The greatest depth reached was five 

 statute miles. The Americans have recorded a greater depth, 

 viz. 5 J miles, or 4620 fathoms. Even greiter depths than this 

 have been given ; but they are not now considered reliable, by 

 reason of the imperfect machinery which was formerly used for 

 sounding. 



The Proceedings of the Royal Society for 1873-1S77 contain 

 many "Preliminary Reports" by Sir Wyville Thomson and the 

 other naturalists attached to the Challenger expedition ; so that 

 all the scientific world were from time to time kept informed of 

 the progress and results of this great national undertaking. 



During the last of our arctic voyages, in 1S75, I had, through 

 the influence and energy of the Royal Society, another oppor- 

 tunity of exploring a part of the North-.-vtlaatic sea-bed which 

 w.as not within the limits of the Ch illenger expedition ; and I 

 was intrusted with the scientific charge of the sounding and 

 dredging conducted in H.M.S. Valorous between Bantry Bay 

 and Hare Island in Davis Strait. This ship accompanied the 

 Alert z.'cii. Discovery on their way northwards. After a voyage 

 of three months, which was rendered m ire eventful by a cyclonical 

 storm and a partial shipwreck on the coast of Greenland, we 

 succeeded in w'orkiug sixteen station-, with depths of from 20 to 

 1785 fathoms. Here also, and even in the midst of icebergs, 

 submarine life sliowed no dcminution in number or extent. 



To this short recital of our later expeditions I must not omit 

 to add a notice of the valuable and suggestive researches which 

 \\ ere accomplished under cou.iderable difficulties by Dr. Wallich 

 in H.M.S. Bulldog m 1S60, while she was engaged in surveying 

 the North- Atlantic sea-bed for the purpo.^e of establishing tele- 

 graphic communication between this cou:itry and North America. 

 The results of these researches were published in Dr. Wallich's 

 important work, entitled "The Norih-Atlantic Sea-bed; com- 

 prising a Diary of the Voyage o.t board H.M.S. Bulldog in 

 1S60, and observations on the presence of Animal Life, and the 

 Formation and Nature of Organic Deposits at Great Depths in 

 the Ocean." On the return voyage, about midway between 

 Cape Farewell and Rockall, tliirteen starfishes came up from a 

 sounding of 1 260 fatli oms, ' ' convulsively embracing a portion of 

 the sounding-line which had been payed out in excels of the 

 already ascertained depth, and rested for a sufficient period at 

 the bottom to permit of their attaching themselves to it." 



A short voyage in H.M.S. Sheaiivatcr \\\xow^ the Mediter- 

 ranean in 1S71 enabled Dr. Carpenter to have some dredging 

 between Sicily and the northern coa t of Africa, on the Adven- 

 ture and Skerki Banks. 'Ihis dredging was by no means un- 

 productive; but the depths did njt exceed 200 fathoms, which 

 we are now inclined to call "shallow waler" ; Dr. Carpenter's 

 word was "shallows." Fifty years ago such depths would 

 have been regarded by naturalists as peculiarly "abysal"! 



The elaborate re|)ort of my lamented friend Prof. Edward 

 Forbes, on the investigation of British Marine Zoology by 

 means of the dre^Ige, w liich he submitted to the British Associa- 

 tion for the Advancement of Science in 1850, and to which I 

 contributed as a humble fellow worker, was preceded by his 

 equally valuable " Report on the Mol!u-ca and Radiata of the 

 Aegean Se:, and on their Distribution, cj sidered as bearing on 

 Geol >gy." The la t-mentimel Report wis puMished by the 

 As-ociation in 1844. Forbes's concIu4oa that the sea-bottom at 

 a depth of 300 fathoms is lifeless because he found that life 

 dimini-hed g.-ajually, and almo t ce.ise I when he dredged at 230 

 fathoms, has certainly been [.roved to be inaccurate as regards 



