520 



Mr. E. 0. C. Baly on the 



with most of the observed points marked with a cross, many 

 of which are double. This curve has been plotted on a much 

 larger scale, and as it is likely to prove of use in any work 

 connected with liquid air, the following points read therefrom 

 will serve for its reproduction : — 



Temperature 



Percentage of 



Temperature 



Percentage of 



(absolute). 



Oxygen. 



(absolute). 



Oxygen. 



o 

 77-54 



0-00 B.P. of Nitrogen. 







78-0 



218 



85-0 



44-25 



78-5 



4-38 



85-5 



48-17 



791) 



6 80 



86-0 



52-19 



79-5 



9-33 



86-5 



56-30 



80 



J 2-00 



87-0 



60-53 



805 



14-78 



87'5 



64-85 



810 



17-66 



88-0 



69-58 



81-5 



21-22 



88-5 



74-37 



82-0 



23-60 



890 



79-45 



82-5 



26-73 



89-5 



84-55 



830 



29-95 



900 



89-80 



88-5 



3335 



90-5 



95-10 



84-0 



3686 



90-96 



100-00 BP. of Oxygen. 



84-5 



40-45 







If the above points be plotted and the curve drawn, the 

 complete relation will be obtained, and the temperature of 

 boiling air can be read direct therefrom if the composition of 

 the gas evolved be found. 



In order to further investigate the subject, a similar series 

 of experiments was carried out in connexion with the com- 

 position of the liquid phase and its relation to the temperature. 

 The samples were taken by means of a finely drawn piece of 

 capillary tubing which dipped into the liquid. This was 

 connected with a filter-pump which was kept running during 

 the experiments. Samples of the gas were taken from a 

 T-piece between tbe capillary and the filter-pump. The 

 liquid air did not fractionate in the capillary, but boiled 

 rapidly away as it rose in the tube out of the vacuum-jacket ; 

 and samples were thus obtained of the mixture of oxygen and 

 nitrogen which composed the liquid. Readings were taken 

 as before on the thermometer, and the experiments were 

 carried out, generally speaking, as in the case of the vapour 

 phase above described. The results obtained were plotted, 

 percentages of oxygen against temperature, and the curve 

 thus obtained is shown on fig. 2 (curve B) . 



