136 REPORTS ON INVESTIGATIONS AND PROJECTS. 



published. A paper on antimony-tin alloys is in press. In the zinc- 

 tin alloys the solid phases are pure zinc and a solid solution containing 

 7 per cent of zinc. In the zinc-cadmium alloys two sets of solid 

 solutions occur with 5 and 96 per cent zinc. Pure zinc and pure 

 lead crystallize from zinc-lead melts. With zinc and bismuth the 

 solid phases are pure zinc and a solid solution containing 3 per cent 

 of zinc. Work is now being done on the possible allotropic forms 

 of zinc. In the antimony-tin alloys there are four series of solid 

 solutions and no compounds. The third series, counting from the 

 antimony end, is instable below 310 . The constitution of the 

 copper-aluminum alloys has been determined over the range o to 65 

 per cent Cu. Experiments on the tensile strength of antimony-zinc 

 alloys show that the maximum strength comes just where it should, 

 at 50 per cent Al. 



Baskerville, Charles, College of the City of New York, New York. 

 Grant No. 237. Continuation of investigation of the rare earths. 

 (For first report see Year Book No. 3, p. 105.) $2,000. 



Professor Baskerville submits the following abstracts of the several 

 investigations carried out with the aid of grants from the Carnegie 

 Institution of Washington. 



ON THE ATOMIC WEIGHT OF CAROLINIUM. 

 Charles Baskerville with Fritz Zerban. 



The investigation on the complexity of thorium was continued. 

 It had been shown by previous experiments that thorium chloride, 

 under certain conditions, may be fractioned into three substances of 

 different volatility. The elements corresponding to these chlorides 

 have been designated as berzelium, new-thorium, and carolinium. 

 Baskerville and Davis had found the atomic weights of the new ele- 

 ments to be 212, 220, and 256, respectively. In a previous report by 

 the junior author these figures were redetermined as being 212.3 for 

 berzelium and 258 for carolinium. 



In continuing the experiments about 100 grams of pure thorium 

 oxide were separated into the three components by the method pre- 

 viously used. About 15 grams of carolinium oxide were obtained 

 from the residues non-volatile at 760 ° C. A determination of the 

 atomic weight of this material was started but not completed by the 

 junior author. The method used for this determination was very 

 similar to that described in the last report. The carolinium chlo- 

 ride was purified in the same way by evaporating with hydrofluoric 

 and sulphuric acids repeatedly. The resulting sulphate was dis- 



