J. Dewar — Boiling Point of Liquid Hydrogen. 301 





Table II. 







Thermometer 

 No. l. 



Thermometer 

 No. 2. 



Alteration 

 of T. 



j at B.P. of 

 1 at B.P. of H 



2i° 



6° 

 17° 



1 ° 



Too 



( at B.P. of 



P 



( at B.P. of H 



C-280 

 mm. 



n 



0-285 

 mm. 



n 



0-280 



mm. 



n 



0-282 



mm. 



n 



i° 



To 



( at B.P. of 



P ° 



( at B.P. of H 



0-842 



mm. 



n 



3-79 



mm. 



n 



0-839 



mm. 



n 



3-76 

 mm. 



n 



i ° 



10 



j at B.P. of 

 1 at B.P. of H 



0-88 per cent. 



2-57 



2-00 per cent. 



5-81 " 



i ° 



100 



can have then an equal addition to the hydrogen value must 

 follow, making it then — 252° or 21° absolute. In a future 

 communication the temperature of solid hydrogen will be dis- 

 cussed. 



I am indebted to Mr. J. D. H. Dickson, M.A., of St. 

 Peter's College, Cambridge, for help in the theoretical discus- 

 sion of the results, and to Mr. Robert Lennox, P.C.S., for able 

 assistance in the conduct of the experiments. 



A.M. Jour. Sci.— Fourth Series, Yol. XI, No. 64.— April, 1901 

 20 



