464 Prof. Wyville Thomson on some of the Results of 



crater and walked for about three miles over the nearly level lava of the 

 eruption of 1868 ; we then clambered up to the ridge overlooking the 

 two liquid lava-lakes, which have remained nearly in the same condition 

 since 1868. "We were greatly struck with the fluidity of the melted 

 lava, which washed about in the basins with very much the appearance 

 and sound of water. The night was perfectly still ; and it had a most 

 singular effect to see the two glowing lakes tossing like the sea in a 

 storm, and a red surf dashing against the encircling rocks and springing 

 forty or fifty feet into the air in wreaths of fiery spray. Lieutenant 

 Bromley and I recrossed the lava-bed after nightfall, and our guide 

 missed the ordinary path. In several places on either side of us the 

 surface of the lava was glowing of a dull red, and we could see through 

 the cracks the crust red-hot a couple of inches under our feet, and the 

 liquid lava flowing beneath at the depth of about half a yard. 



Observations were made by Lieutenant Bromley in the crater and on 

 its rim with the " Fox " dip-circle for inclination and intensity, and with 

 the prismatic compass for declination. Several excellent photographs of 

 the crater were taken during the day. "We returned to the ship on the 

 evening of the 16th, and on the 19th we left Hilo and proceeded under 

 sail for Tahiti, 2270 miles distant. 



In the section between Hawaii and Tahiti, running almost directly 

 southwards, we established 18 observing-stations at average intervals of 

 160 miles. At each of these stations the depth was taken, the bottom 

 temperature was observed with two thermometers, a fair sample of the 

 bottom was obtained, a specimen of the bottom- water was brought up 

 for examination, serial temperature observations were made to a depth 

 of 1500 fathoms, and at eight stations the trawl or dredge was sent 

 down six times successfully, and twice unsuccessfully. Except at one 

 station close to Tahiti, where the depth was 1525 fathoms, the depth 

 ranged throughout the section from 2000 to 3000 fathoms, with a mean 

 of about 2600 fathoms, and the nature of the bottom was very uniform. 

 Except in the neighbourhood of the groups of volcanic islands, where it 

 was found to be largely composed of volcanic debris and shore mud, it 

 consisted mainly of red clay, in many of the soundings containing a large 

 admixture of the decaying shells of Eoraminifera, and in almost all in- 

 cluding a large proportion of manganese peroxide in the form of con- 

 cretions, from the size of a nut to that of an Orhulina, and passing into 

 fine, almost microscopic granules visible under a low power in every 

 sample of sounding. In two patches the siliceous skeletons of Eadio- 

 larians were so abundant as almost to entitle the deposit to the name of 

 " Eadiolarian ooze ;" and a patch between these, nearly halfway between 

 Hawaii and Tahiti, in its abundance of surface Eoraminifera approached a 

 true " Globigerina-oozQ." The larger samples of bottom brought up in 

 the dredge or trawl had, of course, the same general character as the 

 contents of the " Bailie " sounding-tubes ; but in these large manganese 



