390 Scientific Intelligence. 



As further evidence of the unity of thorium, G. Eberhaed has 

 made a careful study of the arc spectrum of many samples of 

 thorium material, including fractions made by a process of crys- 

 tallization by the late Dr. Drossbach, fractions of the chloride by 

 R. J. Me}^*, and other preparations from thorite, fergusonite, 

 yttrialite, and uraninite, and he has found no evidence that any 

 separation of thorium into several components has taken place, 

 or has even been begun. He concludes that the results of his 

 observations show that any element different from the old thorium 

 could be present in these samples only in very insignificant quan- 

 tity. — Berichte, xxxviii, 817, 826. h. l. w. 



4. Nitroxyl Chloride. — According to the results of several 

 investigators, the acid chloride N0 2 C1 has been supposed to have 

 been prepared, by the action of chlorine upon N0 2 , by the action 

 of chlorine upon silver nitrate, and the reaction of N0 2 with 

 PC1 B . Other investigators have been unable to confirm the exist- 

 ence of this compound, and now Gutbier and Lohmann have 

 made an elaborate series of experiments using all the suggested 

 methods of preparation, and they have arrived at the conclusion 

 that this "chloride of nitric acid " has not yet been produced. — 

 Jour, prakt. Chem., lxxi, 182. h. l. w. 



5. The Heusler Magnetic Alloys. — These alloys consist of man- 

 ganese, aluminium and copper ; which under suitable proportions 

 and conditions of temperature shows a magnetic state comparable 

 with that of cast iron. E. Gumlich has made a careful study of 

 two specimens of the following constitution : 



1. Cu 61-5 per cent, Mn 23'5 per ct, Al 15 per ct, Pb 0*1 per ct. 



2. Cu 67-7 " Mn 20-5 " Al 10*7 " Pb 1'2 " 

 The magnetic measurements were made with cylindrical rods 

 18 cm long and 0*6 cm diameter. Since the molecular conditions 

 under changes of temperature promised to throw the most light 

 upon this remarkable manifestation of magnetism in an aggrega- 

 tion of non-magnetizable metals, Gumlich submitted the alloys 

 to a considerable range of temperature during the magnetic meas- 

 urements. At the temperature of liquid air no marked change 

 was observed. Considerable changes, however, ensued on rais- 

 ing the temperature of the alloys. With a field strength of 

 H = 150 the flux of induction was noticeably greater in alloy 1, 

 which contained the larger proportion of manganese and the 

 smaller proportion of lead. The rods were submitted first to a 

 temperature of 79° in alcohol steam for nine hours, and afterwards 

 to 110° (melting point of toluol) for 27 hours. Rod 1 showed no 

 marked change ; but in the case of rod 2 there was a marked 

 change of flux of induction, coercitive force, residual magnetism, 

 and maximum permeability. L. Austin finds that the alloy 

 resembles the magnetic metals in its volume-changes in a strong 

 magnetic field. — Ann. der Phys., No. 3, 1905, pp. 535-550. j. t. 



6. A High Frequency Alternator. — W. Duddell describes an 

 alternator which was primarily used in experiments on the 

 resistance of an electric arc in which the interesting result was 



