ï 



he following pages contain a resumé of my researches on the com- 

 pounds of samarium. I had also intended to prepare and examine the 

 metal, but the quantity of pure oxide of samarium at my disposal was 

 not sufficient. On completing the separation of the oxides, which ac- 

 company the oxide of samarium, I expect to obtain a considerable addi- 

 tional quantity of the latter. 



I have endeavoured to determine the specific gravities of the 

 compounds of samarium, wherevei- the properties of the substances ren- 

 dered an accurate determination possible. The determinations were all 

 made in a perfectly uniform manner viz. by weighing in benzol, care being 

 taken in each case to determine the specific gravity of the benzol and 

 of the substance at the same temperature. Every determination was 

 carefully made, and I believe therefore that the accuracy of the results 

 may be relied upon. 



In the case however of certai)i anhydrous and very hygroscopic 

 salts, obtained by heating the crystallised salts, great accuracy could 

 not be attained. 



In carrying out these researches I have been assisted by Mr. 

 L. I. Eriksson who made several of the analyses and some of the spe- 

 cific gravity determinations, for which I gladly take this opportunity of 

 thanking him. 



The crystalline forms of several of the salts of samarium have 

 been determined by Mr. Hj. Sjögren who will publish a more complete 

 account of his researches later on. 



In order to make this paper a complete monograph, I have in- 

 cluded in it the most important facts contained in a paper on samarium 

 published by me some time ago '). 



') Journ. of the chemical society M CCXLIX, aug. 1883. Ofversigt af K. Sv. 

 Vet. Akad. Förhandl. 1883, JV« 7 p. 17. 



Nova Acta Eeg. Soc. Sc. Dps. Ser. III. 1 



