APPENDIX III. 499 



- 119-8 and - 121-6, mean - 121 at a pressure of 50-6 atmospheres. The 

 vapour tension of liquid argon at - 128 0> C, is 38'0 atmospheres, at - 187 

 it is one atmosphere, and at 189*6 it solidifies to a colourless substance 

 like ice. The specific gravity of liquid argon at about - 187 is nearly 1-5, 

 which is far above that of other liquefied gases of very low absolute boiling 

 point. 



The discovery of argon is one of the most remarkable chemical acquisi- 

 tions of recent times, and we trust that Lord Eayleigh and Professor Ramsay, 

 who made this wonderful discovery, will further elucidate the true nature of 

 argon, as this should widen the fundamental principles of chemistry, to which 

 the chemists of Great Britain have from early times made such valuable 

 contributions. It would be premature now to give any definite opinions 

 upon so new a subject. Only one thing can be said ; argon is so inert that 

 its role in nature cannot be considerable, notwithstanding its presence hi the 

 atmosphere. But as the atmosphere itself plays such a vast part in the 

 life of the surface of the earth, every addition to our knowledge of its compo- 

 sition must directly -or indirectly react upon the sum total of our knowledge 

 of nature. 



