41 219 



was pushed on the rest of the glass tube, while it still remained under the mercury, 

 in order to prevent atmospheric air getting into the bottle. Then the other end 

 of the bottle was immersed in the mercury, and knocked off in the same way. 

 This end of the bottle was then connected, by means of an indiarubber tube, with 

 a mercury resei'voir that could be raised and sunk to adjust the pressure of the gas 

 in the bottle. Of course, care was taken that the indiarubber tube was quite filled 

 with mercury before it was pushed on the glass tube. The other tube of the col- 

 lecting bottle, that which was first broken, was then connected, by means of the 

 above mentioned indiarubber tube, with the entrance tube of the measurer, and we 

 were ready to conduct the gas under investigation from the bottle into the measuring 

 tube. I endeavoured, by keeping the mercury reservoir in a suitable position, to 

 avoid rarefaction of the gas in the bottle, so that possible small leakages in the 

 indiarubber connection could not result in a mixture of atmospheric air with the 

 gas examined. As it was a very difficult matter to force the air completely out 

 of the measuring tube and the accompanying inlet tube by means of mercury, 

 the remaining atmosphere was excluded by washing the measurer a few times 

 with small quantities of the gas, before the gas to be used for analysis was 

 introduced. 



The subsequent conduct of the analysis was roughly as follows. The sul- 

 phuretted hydrogen was first absorbed by a small globe of pure peroxide of man- 

 ganese moistened by thick phosphoric acid. The absorption took place above 

 mercury in an absorption pipette. Then the carbon dioxide was absorbed by a 

 strong solution of caustic potash, and the oxygen was destroyed by a solution of 

 pyrogallic acid in a solution of caustic potash. This solution was made according 

 to a prescription of Hempel ', by mixing 5 grams of pyrogallic acid dissolved in 

 15 ccm. of distilled water with 120 grams of hydroxide of potassium dissolved in 

 80 ccm. of distilled water. 



After having measured the volume of the remaining gas, a known amount of 

 oxygen or air, and if necessary a mixture of 2 volumes of hydrogen and one 

 volume of oxygen, was admitted, and the gases mixed brought to explosion in the 

 explosion pipette. After the explosion the remnant gas was examined for carbon 

 dioxide and oxygen in the same way as before. Of course the gas after every 

 absorption was drawn back to the measuring tube and its volume determined. 

 By repetition of the test I made sure of a complete absorption in every case. 



4. luvestigatiou of the rare inactive gases contained in the spring gases. 



The bottles containing the gas collected for investigation of the rare, inactive 

 gases, were opened in the same way as the other collecting bottles, except that in 

 this case 1 employed water instead of mercury to shut out tlie air. 



I used the arrangement shown in Fig. 10 in the subsequent treatment of the 



- Hempel: Gasanalytische Methoden, 3. Aufl. 1900, p. 133. 



U. K. I). Viilensk, Selsk. Skr.. 7. Hiflilie, naluividensU.ii(< TiKillicm. Afil. VIII 4, 29 



