BY THE PRESIDENT. 175 



w:i^ undertalccu by Professor "VVyvillc Thomson, auci extended from 

 tlie south of Ireland to what is probably the deepest part of the 

 North Atlantic in the European seas. The 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 area, including the 

 Shetland Isles ; the greatest depth was 867 fathoms. In the 

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

 disposal of the Eoyal Society for further exploration. This 

 expedition was divided into two cruises, North Atlantic and 

 Mediterranean. The former was assigned to me, and comprised 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. Carpenter, and extended 

 round Sicily. There were 29 stations, at depths ranging from 51 

 to 1743 fathoms. Professor 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 culminated in the 

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

 commenced on the 21st of December, 1872, and ended on the 24th 

 of May, 1876, having thus occupied a period of three years and five 

 months. Dnring 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 3875, and of trawlings from 10 to 

 3050 fathoms. The greatest depth reached was five statute miles. 

 The Americans have recorded a greater depth, viz. five miles and a 

 quarter, or 4620 fathoms. Even greater 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 lioyal Society' for 1873-1877 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 1875, I had, through the 

 influence and energy of the Royal Society, another opportunity of 

 exploring a part of the North- Atlantic sea-bed which was not within 

 the limits of the ' Challenger ' Expedition ; and I was entrusted with 

 the scientific charge of the sounding and dredging conducted in 



