xxil THE LIFE OF KARL WILHELM SCHEELE 



cut short in the prime of his manhood, it is now impossible 

 to say what other discoveries he would have made dis- 

 coveries which may at the present day still remain to be 

 discovered. The inherent difficulties in the analysis of fluor 

 spar are still great, and it is only within a few years ago that 

 fluorine has been isolated, and even this isolation was doubted 

 by sceptical English chemists, until the eminent French 

 chemist Moissan convinced his doubting British confreres by 

 ocular demonstration. 



His LATER ESSAYS. 



1774. Chlorine. Colouring and decolorising glass by Man- 

 ganese. His experiments on the black oxide of manganese 

 were given to the world in this year. During these experi- 

 ments he discovered chlorine, and, as we have already spoken 

 on the importance of that discovery, little remains to be said. 

 Suffice it to say that Tennant, Weldon, Deacon, etc., have only 

 followed up Scheele's discovery. Of the bleaching and disin- 

 fecting properties of chlorine it is unnecessary to speak, and it is 

 pleasing to notice that its merits in the form of chloride of lime 

 are once more coming to the fore as a disinfectant ; and had a 

 sufficient supply been sent to the army and medical authorities 

 in South Africa in proper time, there would have been fewer 

 deaths from enteric fever. Scheele, moreover, during his ex- 

 periments on manganese discovered baryta, and differentiated 

 between the green arid purple compounds of manganese with 

 potash, and was able to explain how manganese colours and 

 decolorises glass. 



1775. Benzoic Acid. In regard to this experiment the 

 reader is referred to the Essay, p. 137, which speaks for itself. 



Arsenic Acid. Scheele was the first to examine arsenic 

 acid. 



