1875.] Cruise ofH.M.S. ' Challenger.' 37 



On the 23rd we sounded in 2875 fathoms, and on the 24th in 2775, 

 the bottom in both cases having much the same character which it had 

 maintained throughout the cruise. The Albatrosses, which had followed 

 the ship, to the number of from fourteen to twenty daily, since we left 

 Japan, left us to-day. We saw one or two Boatswain Birds {Phaeton rubri- 

 cauda), and a Turnstone (Strepsilas intevpres) flew about the ship for some 

 hours, lighting on the combings and the rigging. On the 26th we sounded 

 in 2225 fathoms ; and on the morning of the 27th we passed into the 

 strait between the islands of Molokai and Oahu, and trawled on hard 

 ground in 310 fathoms, with but little success. In the evening we anchored 

 in the harbour of Honolulu. 



This cruise naturally divides itself into two parts : — a section about 3170 

 nautical miles in length, including the stations from No. 237 to No. 253, 

 very slightly to the northward of east, between the parallels of 35° and 

 38° N. lat. ; and a meridional section of 1128 nautical miles, along the 

 meridian of 155° W. long. The first of these sections corresponds very 

 closely in relative position with the section in the Atlantic between Sandy 

 Hook and the Agores, and .the points of resemblance and difference 

 between them, when fully worked out, must prove most instructive. The 

 two sections cross the two great deflections to the northward of the 

 equatorial current, in the Atlantic the Grulf-stream, and in the Pacific the 

 "Kuro-Siwo;" and the thermic influence of the two currents is fairly 

 contrasted. The influence of the Grulf-stream, if not absolutely greater 

 (and this is a point which it will be somewhat difficult to determine), is at 

 all events much more concentrated and effective, owing to the continuity 

 of the coast-line of the American continent, to the way in which the 

 water of the equatorial current is driven into the Grulf of Mexico and 

 superheated there, afterwards to be kept together and ejected in a defined 

 stream through the Strait of Florida, and to the absence of periodical 

 winds in the Atlantic. In the Pacific, on the other hand, the main flow 

 of the equatorial current is weakened among the passages of the Malayan 

 archipelago ; and although a large part of it is directed northwards by 

 the broken barrier formed by the Fiji Islands, the New Hebrides, and 

 Papua, it almost at once enters the region of the monsoons, where it is 

 thwarted for half the year ; and it can only be regarded as comparable 

 with that portion of the reflux of the Atlantic equatorial current which 

 passes outside the West-Indian Islands. Nevertheless it passes the south 

 coast of Japan as a very palpable and apparently a permanent current, 

 exercising a very perceptible thermic influence to a depth of at least 300 

 fathoms. 



In traversing the Pacific the influence of the Japan current appears to 

 be gradually lost ; while I am still inclined to believe that in the Atlantic 

 the Grulf -stream is banked down against and reflected from the western 

 coast of Europe. It is a question of great complexity ; but it seems to 

 me that it is consistent with our experience that the temperature of the 



