42 



Drs. Ramsay and Young on 



Olszewski and by "Wroblewski, but their results do not agree 

 well together. Olszewski measured his temperatures by means 

 of a hydrogen-thermometer; Wroblewski by a thermopile. 

 It was found that the curve showing the relation of tempe- 

 rature to pressure was very fairly regular when constructed 

 from Olszewski's numbers, and the temperatures correspond- 

 ing to definite pressures were therefore read from this curve. 

 The temperature corresponding to a pressure of 9 millim. is 

 a single observation by Olszewski. The temperatures corre- 

 sponding to 50, 100, and 150 millim. are taken from Wro- 

 blewski's results. 





Katios. 



Absolute temperatures 

 of Oxygen. 



Pressures. 



















From observed 



Smoothed. 



Eecalculated. 



Observed. 





temperatures. 









millim. 







o 



o 



9 



4-5967 



4-454 



63-5 



61-5 



50 



4-0534 



4-349 



716 



76-8 



100 



3-9358 



4-2845 



75-8 



82-5 



150 



4-0132 



4-253 



78-6 



83-0 



300 

 400 





4191 



4-182 



83-2 

 85-1 





,,., 



500 





4-1405 



87-4 





600 





4-120 



89-0 





700 





4-1025 



90-4 





800 



4070i* 



4090 



91-6 



920 



1000 



40732 



4-064 



93-7 



93-5 



1500 



4-0536 



4-0175 



97-9 



970 



2000 



4-0520 



3-980 



101-1 



1000 



3000 



3-9478 



3924 



106-1 



1055 



5000 



3-8267 



3-849 



113-2 



113-9 



10000 



3-7044 



3-733 



124-7 



125-7 



15000 



3-6489 



3-656 



132-7 



1330 



20000 



3-6242 



3-5975 



139-1 



138-1 



It is hardly to be expected that the measurement of such 

 extremely low temperatures could be very exact, and the 

 difference of 2°*0 at an absolute temperature of about 60°, is 

 not more than might be expected. It will be seen that the 

 three temperatures given by Wroblewski differ considerably 

 from those calculated from Olszewski's results. 



The vapour-pressures of oxygen are given up to the critical 

 point, at which the pressure is 38,600 millim., but those of 

 water have only been determined up to 20,000 millim. The 

 absolute temperatures of oxygen were therefore compared 

 with those of alcohol, in order to find whether the value of c 

 remains constant up to the critical point. 



