RECENT ADVANCES IN SCIENCE 125 



sufficient to establish the origin of the lines to be helium, 

 refers briefly to some work of his own, now in progress, which 

 would allocate some of these lines to hydrogen, and so support 

 the traditional view. 



INORGANIC CHEMISTRY. By C. Scott Garrett, B.Sc, University, 

 Liverpool. 



Owing to the present great crisis in the affairs of the European 

 nations it is only to be expected that the world's output of 

 purely scientific communications will in the meantime be con- 

 siderably curtailed. This state of things is unhappily being 

 realised at the present juncture, for, with a notable exception 

 in the case of America, the energies of men of science are 

 being more and more diverted from their accustomed channels 

 into those of direct national utility. It is for these reasons 

 that we are unable to record any very striking advances in 

 the domain of pure inorganic chemistry during the past 

 quarter. 



Of the work emanating from American schools that dealing 

 with the atomic weight of lead is probably first in point of 

 importance. In view of the extensive new field opened up by 

 Soddy's recent work on the end-products of the radioactive 

 degradation of the elements in which lead figures very largely, 

 and which has enabled him as well as Fajans to propound the 

 theory of Isotopism, this work of Baxter and his colleagues 

 makes a very timely appearance {Jour. Am. Chem. Soc. 191 5, 37, 

 1020). 



The investigations, carried out with all the precision and 

 refinement of the Harvard school, have resulted in an even 

 value for the atomic weight of common lead amounting to 207*20 

 if Ag = 107*880, or 207*18 if Ag= io7"870. 



Eleven different mineralogical sources, as wide apart as 

 Australia, Germany, and the United States, provided the 

 starting material, and the different specimens of lead obtained 

 from the minerals, when converted into chloride or bromide, 

 all gave identical spectra. Further, no appreciable radioactivity 

 could be detected in any of the specimens, and the authors 

 conclude that there is no evidence that common lead contains, 

 either wholly or in part, isotopes of different atomic weight. 

 It should be noted, however, that while this work increases 

 slightly the generally accepted value for the atomic weight of 



