CHEMISTRY — BASKERVILLE. 143 



we have extracted from it a small percentage of an oxide which 

 responds to all the known chemical tests for thoria. However, it 

 possesses no radioactivity whatever. 



This observation is of unusual interest, for if it be thorium, then 

 the advanced theories of Rutherford and Soddy as to the inherent 

 radioactivity of thorium and its so-called disintegration are no longer 

 tenable and must be rejected. If it be not thorium, then we have 

 a new element, whose compounds resemble that element very closely 

 and may prove to be one of the constituents the author has reported 

 present in the usually accepted element of thorium. To determine 

 this, atom weight determinations and the spectrum must be had. 

 The former will be worked upon as soon as we shall have extracted 

 sufficient of the material, as that already obtained has been turned 

 over to Sir William Crookes, of London, and Dr. G. Eberhard, of 

 the Royal Astrophysical Laboratory at Pjotsdam, who will make the 

 spark and arc spectra, respectively. 



ON THE COBALT-AMINES OF THE COMPONENTS OF THORIUM. 

 Charles Baskerviu.e with E. E. Randolph. 



Wolcott Gibbs found that luteo cobalt precipitated completely 

 the four cerite earths — cerium, lanthanum, praseodymium, and neo- 

 dymium — as neutral double sulphates. With this reagent he effected 

 a separation of these four earths from erbium, yttrium, and ytter- 

 bium. He reported that luteo-cobalt-amine gave with solutions of 

 thorium salts a " heavy fine yellow crystalline precipitate very diffi- 

 cultly soluble in cold water and practically insoluble in hot water." 

 At his suggestion a study of the conduct of the various fractions 

 with these cobalt-amines was undertaken. The outcome, as noted 

 below, was most satisfactory and our thanks are due this distinguished 

 pioneer in research in the rare-earth field. 



Chlorides, nitrates, and sulphates of the fractions were prepared 

 from the material obtained by Baskerville and Davis (J. Am. Ch. S., 

 26, 922). Neutral as well as slightly acid solutions were used. In 

 all cases of comparison the conditions as to acidity, temperature, con- 

 centration, and the amount of solution and of reagent used were 

 kept rigidly the same. Neither the chloride nor the nitrate of the 

 original thorium or caroliuium gave a precipitate with either of the 

 cobalt salts used. There was no apparent difference between the 

 action of the cobalt- amines and the neutral and weakly acid solutions 

 of any of the salts. 



Luteo and roseo cobalt-amines gave precipitates with the sulphate 

 of the berzelium fraction, and formed characteristic crystalline double 



