ANALYSES OF BOTTOM DEPOSIT. 



By Dr. Charles J. J. Fox. 



Prof. Nansen brought me what was left over of Samples 10, 10a, 10c, 

 with the request that 1 would carry out a few analyses just to obtain some 

 idea of the order of accuracy of the methods as employed above by Dr. 

 Heidenreich. Sample No. 10 was in three portions, one being distinctly 

 brownish another brownish grey and the third one grey. They are referred 

 to here as 10 1 10 2 10 3 respectively. The samples as brought to me were 

 from 6—8 gms. each, and therefore really too small to allow of as complete 

 an investigation of this obviously important point, as would have been desirable. 



After due consideration it was decided to estimate in each sample, the 

 Ferrous and Ferric Oxides and in addition, in the cases of samples Nos. 10a 

 and 10 c the Lime and Carbonic Acid. These seemed to be the most important 

 constituents and after a short preliminary investigation, it also appeared likely 

 that they could be estimated even on such small samples, with very fair 

 accuracy. 



Some of the samples were in alcohol and some were dry; all were 

 powdered finely and dried in a dessicator for a few days. It then appeared 

 that they were slightly hygroscopic and the weighings had to be done from 

 a closed weighing bottle. Of each sample two quantities of about 2 gms. 

 each were weighed out; the one sample was used for a determination of the 

 Iron (ferrous and ferric) and the Lime, and the other for the Carbonic Acid. 

 The former sample was boiled for some time in an air-free flask with 30 cc. 

 of 20% HCI. After allowing to settle, the liquid was rapidly decanted, the 

 residue washed thoroughly and the washings added to the bulk of the liquid. 

 The whole was much diluted and then titrated with Potassium Permanganate 

 to get the amount of Ferrous iron; pure zinc was added and the whole 



