THE DETECTION AND WIDE DISTRIBUTION OF YTTRIUM. 
899 
Cerite was accordingly the next mineral experimented on. The powdered mineral 
tested in the tube in the original way gave a good citron band. It was made into a 
paste with sulphuric acid, and after all action had ceased it was extracted with cold 
water. The earths were then precipitated with ammonic oxalate, and the oxalate 
ignited. The fawn-coloured powder was then converted into sulphate, dissolved in 
water, and the cerium metals precipitated by long digestion with excess of potassic 
sulphate. When no didymium bands could be detected in a considerable thickness of 
the supernatant liquor it was assumed that all the cerium metals were down, and the 
liquid was filtered. 
23. The precipitated double sulphates were dissolved in hydrochloric acid, and the 
earths precipitated as oxalates. After ignition and treatment with sulphuric acid, the 
mixed ceria, lanthana, and didymia were tested in the radiant matter tube, but the 
merest trace only of citron band was visible. 
24. This experiment proved the inadequacy of the didymium explanation (22), and 
further tests showed that not only could I get no citron band in pure didymium 
compounds, but the spectrum entirely failed to detect didymium in many solutions of 
the earth which gave the citron band brilliantly. 
25. Attention was now turned to the solution filtered from the insoluble double 
sulphates from cerite (22). Potash in excess was added to the filtrate, and the 
flocculent precipitate filtered off, and after well washing was converted into sulphate, 
and tested in a radiant matter tube. The spectrum, of extraordinary brilliancy, was 
far brighter than any I had hitherto obtained. Unfortunately, however, the quantity 
was too small to be subjected to very searching chemical analysis. 
Examination of thorite and orangite. 
26. Search was next made amongst other minerals rich in the rarer earths. 
Thorite, another disputed mineral, was finely powdered, treated with sulphuric acid, 
and tested in the radiant matter tube. It gave the citron spectrum most brilliantly 
—equal, in fact, to the mixture of earths obtained from zircons (18, 21) at so great an 
expenditure of time and trouble. Orangite treated in the same manner gave almost 
as good a spectrum. Pure thorinic sulphate prepared by myself was found not to 
give the citron band, but three specimens prepared and given to me by friends all 
gave it, so it was not unlikely that in thorite and orangite might at last be found a 
good source of the long-sought element—that in fact the body I was hunting for, if 
not thorina, might possibly be Bahr’s hypothetical wasium. Having obtained about 
2 lbs. of orangite and thorite, they were worked up as follows :— 
27. The finely-powdered mineral was heated for some time with strong hydrochloric 
acid, and when fully gelatinised and all action had ceased, it was evaporated to 
dryness to render the silica insoluble ; then extracted with water slightly acidulated 
with hydrochloric acid, boiled, and filtered. Hydric sulphide was passed through the 
