236 Royal Society. 



rose. Captain Hares was most anxious, however, to carry out our 

 object, and the dredge was put over at 5 a.m. "We were surrounded 

 by icebergs ; the wind continued to rise, and a thick snow-storm 

 came on from the south-east. After a time of some anxiety the 

 dredge was got in all right ; but, to our great disappointment, it 

 was empty : probably the drift of the ship and the motion had 

 prevented its reaching the bottom. In the mean time the wind 

 had risen to a whole gale (force=10 in the squalls), the thermo- 

 meter fell to 21 0- 5F., the snow drove in a dry blinding cloud 

 of exquisite star-like crystals, which burned the skin as if they 

 had been red-hot ; and we were not sorry to be able to retire from 

 the dredging-bridge. 



Careful observations on temperature are already in your hands, 

 reported by Captain Nares. The specific gravity of the water has 

 been taken daily by Mr. Buchanan ; and, during the trip, Mr. Bu- 

 chanan has determined the amount of carbonic acid in 24 different 

 samples — 15 from the surface, 7 from the bottom, and 2 from 

 intermediate depths. The smallest amount of carbonic acid was 

 found in surface-water on the 27th January, near Kerguelen ; it 

 amounted to 0*0373 gramme per litre. The largest amount, 

 0*0829 gramme per litre, was found in bottom-water on the 14th 

 February, when close to the Artarctic ice. About the same lati- 

 tude the amount of carbonic acid in surface-water rose to the 

 unusual amount of 0*0656 gramme per litre ; in all other latitudes 

 it ranged between 0*044 and 0*054 gramme per litre. From 

 the greater number of these samples the oxygen and nitrogen 

 were extracted, and sealed up in tubes. 



The considerations connected with the distribution of tempera- 

 ture and specific gravity in these southern waters are so very com- 

 plicated, that 1 prefer postponing any general resume of the 

 results until there has been time for full consideration. 



While we were among the ice all possible observations were 

 made on the structure and composition of icebergs. "We only 

 regretted greatly that we had no opportunity of watching their 

 birth, or of observing the continuous ice-barrier from which most 

 of them have the appearance of having been detached. The 

 berg- and floe-ice was examined with the microscope, and found 

 to contain the usual Diatoms. Careful drawings of the different 

 forms of icebergs, of the positions which they assume in melting, 

 and of their intimate structure were made by Mr. Wild * and 

 instantaneous photographs of several were taken from the ship. 



Upwards of 15,000 observations in meteorology have been 

 recorded during the trip to the south. Most of these have already 

 been tabulated and reduced to curves, and otherwise arranged for 

 reference in considering the questions of climate on which they 

 bear. 



Many specimens in natural history have been stored in about 

 seventy packing-cases and casks, containing, besides dried speci- 

 mens, upwards of 500 store-bottles and jars of specimens in spirit. 



I need only further add that, so far as I am able to judge, the 



