of Edinburgh, Session 1884 - 85 , 
153 
tative research would have to be undertaken before any definite 
conclusion as to the true nature of these bodies could justifiably be 
drawn. Only the title of our paper was therefore published in the 
Proceedings of this Society.* The old University Laboratory being 
in many respects unfitted for the prosecution of accurate quantita- 
tive work, our researches were repeatedly postponed in the hope of 
being able to continue them in the new University Laboratory, 
which, however, only now approaches completion. This delay has 
been to us a subject of much regret, the questions involved being of 
no little interest. 
We have still in our possession specimens of the various prepara- 
tions now nearly five years old. When last examined, viz., during 
the Tercentenary Celebration of the University in April of last year, 
when they, were shown to several of the distinguished visitors, they 
retained their properties to all appearance unchanged. 
A week or two ago we observed a communication by M. 
Lecoq de Boisbaudran,f which commences as follows : — 
“ La recente publication d’un travail etendu de M. Cleve relatif 
4 I’action de l’eau oxyg6nde sur les terres rares (Yt 2 0 3 , Ce 2 0 3 
Th0 2 etc.) in’engage h ne pas poursuivre les essais que j’avais com- 
mences dans la m£me voie. Je me bornerai & exposer ici quelques 
observations se rapportant & la peroxydation de Ce 2 0 3 et de Th0 2 .” 
M. Cleve, in his valuable paper (published January 1885), J which 
deals mainly, though not exclusively, with peroxides of the rare 
earths, refers to a paper by R. Haas, § entitled “ Ueber Peroxyde in 
der Zmc Magnesiumgruppe,” dated 30th September 1884, which 
we had not previously noticed, and which covers very much the 
same ground as our paper, dated 5th July 1880. Under these 
circumstances, the verbatim publication of our paper is rendered 
necessary, in order to maintain our right to continue our researches. 
There can be no doubt that further investigation is very desirable. 
In the first place, Messrs Haas and Clbve state that they have 
not been able to obtain peroxides of aluminium and beryllium by 
means of peroxide of hydrogen. This we claim to have done in the 
case of aluminium, and some preliminary experiments lead us to the 
belief that beryllium also is capable of similar peroxidation. There 
* Yol. x. page 706. + Comptes Rendus. 
+ Bui. Soc. Chim. § Bet, d. d. Chem. G-es. 
VOL. XIII. 
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