8 , JOURNAL OF THE 
precipitation, etc. Such work was quite inadequate to settle 
the question, as Dumas had pointed out that unustial methods 
must be used, or, he might have added, the old methods car- 
ried out to an unusual or exhaustive extent. Certainly, if a 
moderate application of the usual methods was sufficient for 
this decomposition, evidences of it would have been obtained 
long ago by the host of careful workers who have occupied 
themselves over these substances. Crookes has busied him- 
self with the method of fractional precipitation (though not 
with special view to the testing of this question), and applied 
it most patiently and exhaustively to such substances as the 
rare earths, without obtaining results from which anything ~ 
conclusive could be drawn, Victor Meyer seems to have_be- 
lieved that the decomposition could be effected by high tem- 
peratures, and was very hopeful of experiments which he had 
planned before his untimely death. Others have spasmodic- 
ally given a little time to the problem, but no one has 
thought highly enough of it to attack it with all of his en- 
ergy. 
Let us stop a moment and ask ourselves what would be at- 
tained if any one should succeed in decomposing an element 
by one of the usual methods. Has not this been done repeat- 
edly in the past and merely served to add to the list of the 
elements? Didymium has been made to yield praseo-and neo- 
dymium. ‘That which was first called yttrium has been di- 
vided into erbium, terbium and ytterbium, and according to 
Crookes may possibly be still further decomposed. But these 
and similar decompositions are not generally accepted as of- 
fering any evidence that elements can be decomposed. It is 
merely the discovery of one or more new substances which 
have remained hidden in constant association with known 
bodies which were supposed to be simple. It would be nec- 
essary to prove that a single individual element had, by the 
process adopted, been actually decomposed and not some pre- 
existing impurity discovered. This, of course, would be ex- 
ceedingly difficult, and all such attempts as those mentioned 
can have little bearing upon the general question, and can 
hold out slight hope of reward beyond the fame springing 
from the discovery of a new element. 
