CHEMISTRY — baske;rvili.E. 143 



heating oxide in a current of chlorine mixed with vapors of sulphur chloride. 

 The chloride obtained in this way was mixed with one-third of its weight of 

 barium chloride and with suflScient sodium chloride to make up for two 

 molecules of sodium chloride altogether. The barium chloride was added 

 to increase the temperature of the electrolyte ; this peculiar property of 

 barium chloride was discovered by Muthmann. Experiments with the view 

 of electrolizing the double chlorides are in progress. 



A third method which presented itself was the use of metallic calcium as a 

 reducing agent acting in a similar way as aluminum, since calcium is now 

 one of the cheaper metals and can be had in large quantities. A great 

 number of experiments was undertaken, using oxide, anhydrous chloride, 

 double chlorides or fluorides, changing the proportions of the thorium com- 

 pound to the reducing agent, and using outside heat or Goldschniidt's ignition 

 method. In most cases metallic thorium was obtained in the form of a gray 

 powder, but never as a regulus. Although calcium has a higher reducing 

 power than aluminum, the heat of combustion is not sufl&cient to melt the 

 metal as well as the calcium oxide produced. 



INVESTIGATIONS ON METALLIC YTTRIUM, GLUCINUM, CERIUM, AND 



ZIRCONIUM. 



In connection with the experiments on metallic thorium an investigation 

 on some other rare-earth metals was begun. For the material, which con- 

 sisted of pure rare-earth preparations and of 5 pounds of Norwegian gado- 

 linite, we are indebted to the Welsbach Light Company, at Gloucester, New 

 Jersey, and especially to their chemist, Dr. H. S. Miner. 



The gadolinite was treated in the following way : It was ground to a fine 

 powder and decomposed by heating with crude hydrochloric acid. The 

 silica was then filtered off and the solution evaporated to dryness in order 

 to render insoluble that part of the silica which remained dissolved after 

 the first treatment. The residue was dissolved in very dilute hydrochloric 

 acid, the solution filtered again, diluted to about 10 liters, and slowly poured 

 into a solution of 3 pounds oxalic acid in 15 liters of water, and the whole 

 allowed to stand for two days. It was then filtered and washed. The yttria 

 was extracted from these oxalates by Drossbach's method, which consists 

 in dissolving the moist oxalates in a strong solution of potassium carbonate 

 and pouring this solution into a large quantity of hot water, whereby the 

 cerite-earths are precipitated. The filtrate was acidified with hydrochloric 

 acid, which precipitated the oxalates again. These were filtered off, washed, 

 dried, and ignited. In this way a first portion of yttrite earths was obtained, 

 which was further purified by precipitation with ammonia. The hydroxides, 

 after thorough washing, were dissolved in hydrochloric acid. 



The other portion of the double carbonates which was insoluble in water 

 still contained a large quantity of yttrite earths. The precipitate was, there- 



