218 ANOTHER CONSTITUENT 



asserted that there existed in the sun a substance which he called 

 on that account Helium. This element Professor Ramsay now 

 believes he has proved to be not only one of our terrestrial ele- 

 ments, but allied with Argon, the new component of the atmo- 

 sphere. 



There were two or three suspicious characteristics about Argon. 

 In the first place, it was most unsocial — it would combine with no 

 other substance ; and, secondly, it did not fit into Mendeleeff's 

 great law, which connects the weights of the atoms and molecules 

 of matter with their qualities. " So much the worse for the law," 

 said some ; but the older chemists were hardly willing to see the 

 breakdown of one of the grandest generalisations of modern 

 times. Professor Ramsay's discovery probably gets rid of both 

 these suspicions attaching to the new gas. In order to find out 

 whether there was not something in the world with which Argon 

 would keep company, he was examining an extremely rare earth 

 found in Norway, and known as cleveite, after its discoverer, the 

 Swedish chemist, Cleve. When this mineral is treated with weak 

 sulphuric acid, it gives off a gas which hitherto has always been 

 regarded as nitrogen. The Professor found, by very close exami- 

 nation, that it was not nitrogen at all, but Argon ; and, moreover, 

 there was associated with it another gas, which also upon rigorous 

 scrutiny he found to be, to use his own words, " a gas which had 

 not yet been separated." He submitted it to Professor Crookes, 

 who is eminent as a spectroscopist as well as a chemist, and the 

 result is to show almost with certainty that the gas thus found is 

 none other than Helium. Just as the nitrogen of the atmosphere 

 was shown by Lord Rayleigh and Professor Ramsay to hide within 

 it another gas — Argon ; so Argon is now proved to contain ano- 

 ther element until now thought to exist only in the sun. The 

 spectroscope told us that 91,250,000 miles away, on the bright 

 incandescent solar surface, where everything known on earth would 

 be melted into vapour by fervent heat, there was present a gas 

 never met with here ; aud now, by dint of laborious research, the 

 chemist finds it, in an extremely rare earth it is true, but probably 

 a constituent of the atmosphere that supports all terrestrial life. 



The discovery was made and confirmed by Mr. Crookes's 

 spectroscopic examination quite recently. Terrestrial Helium has 



