428 On Dredgings and Deep-Sea Soundings. [June 18, 



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 latitude 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. Prom the greater number of 

 these samples the oxygen and nitrogen were extracted, and sealed up in 

 tubes. 



The considerations connected with the distribution of temperature and 

 specific gravity in these southern waters are so very complicated, that I 

 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 consider- 

 ing 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 specimens, 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 expedi- 

 tion is fulfilling the object for which it was sent out. The naval and the 

 civilian staff seem actuated by one wish to do the utmost in their power, 

 and certainly a large amount of material is being accumulated. 



The experiences of the last three mouths have of course been somew r hat 

 trying to those of us who were not accustomed to a sea-life ; but the 

 health of the whole party has been excellent. There has been so much to 

 do that there has been little time for weariness ; and the arrangements 

 continue to work in a pleasant and satisfactory way. 



(Signed) CHAELES WTTILLE THOMSON. 



