lxiv PROCEEDINGS. 
he was chemist of a silver mining company in the Freiburg district in 
Germany, he met with a constant loss of 7 per cent, in his analyses, and 
a close search with refined methods enabled him to announce to the 
world the new metal Germanium. 
But I have digressed. The matter rested after D’Elhuyar’s time until 
the fame of the two great analysts, Berzelius and Klaproth, induced some 
one to send to each of them a sample of the mineral. These chemists 
soon decided that lime was not the main constituent and that though iron 
was present it was only in mere traces. Both set themselves to solving 
the problem and almost simultaneously announced to the world the 
existence of a hitberto unknown element. There was considerable dis- 
cussion as to which could claim the precedence, but the scientific world 
has yielded the palm to Berzelius by adopting his name, Cerium, instead 
‘of ochroit-erde proposed by Klaproth. In tracing out the history of this 
interesting mineral however, we have really passed the date wheu the 
apple of discord was thrown among the chemical family. The date of the 
‘discovery of an oxide containing the unknown element Ce. was 1804, the 
date of the discovery of the first of the rare earths was 1789 when 
Klaproth isolated Zirconia. If this be disputed, for Zr. does not fulfil 
all the conditions of a rare earth, we must yet anticipate 1804, for in 
1794 Gadolin, a Finnish chemist, gave to the world Yttria, the oxide of 
Yttrium which fulfils in every respect the conditions of our definition. 
‘This element was discovered in a mineral from Ytterby, in Sweden, 
which mineral has since been named in honor of this chemist Gadolinite, 
In 1818 Berzelius announced the discovery of a new oxide, Thoria, 
an some rare minerals from the neighbourhood of Fahlun, Sweden. This 
discovery he confirmed in 1828 when he found the same oxide ina 
mineral from Brewig, in Norway. Before going into the history of the 
very remarkable periol which followed, let us see just what was known 
up to 1835. Ceria, Zirconia, Thoria and Yttria were recognized as dis- 
tinct oxides, each supposed to contain a distinct element. Only one of 
these, however, Yttria, belongs to the rare earths, if we keep to the strict 
letter of our definition. Such, then, was the knowledge of the rare 
earths ; they were ordinary oxides of no more interest than lime or 
baryta, nay, not so much, for they were of no practical use, they were 
rare, and so of no interest except to seekers after curios. 
In 1837-38 a young Swedish chemist, a pupil of Berzelius, took up 
the neglected earths and under his magic touch, for he was a genius, new 
