9 s 



NATURE 



[July 20, 191 1 



All membei - p d nd one me ting i ai h in ai 



wal oi their "spirit power." The life enjoined 

 on the members is a life of rectitude. They are taught 

 that membership dues not exempt a man from the con- 

 sequences of his sins. Lying, stealing, and the use of 

 liquor are strictly forbidden. Various stages ol initiation 

 are described, and the appropriate songs with their music- 

 are given, each of which is accompanied by a reproduc- 

 tion of the mnemonic pictograph. All the songs are re- 

 corded in mnemonics on strips of birch bark, each record 

 serving as a remind-, ,,( the essentia! idea of the song. 

 The following examples illustrate these pictographs. 



The Medicine song, illustrated by a figure, is: " Light- 

 Around you— Chiei Woman." ["he picture was drawn by 

 a woman, who stated that the horizontal line represents the 

 edge of the wigwam, along which are arranged various 

 articles of value indicated l>\ the dots. At each end are 

 torches, the light of which falls on the gathered wealth, 

 causing many of the articles to glitter. These articles 

 belong to a woman standing with upraised hands and 

 wearing a pearl necklace with a locket. In singing this 

 song the woman pointed to one portion of the picture after 

 another, tapping the birch bark lightly as she sang. 



The fourth song (p. 50), for initiation into the Sixth 

 Degree ol the Widewiwin (Grand Medicine Society), is: 

 "Who is this— Sick unto death — Whom I restore to life? " 

 The pictograph represents the body of the person to be 

 initiated, on whom are seen lines representing the 

 "strength" he is to receive through the Aftde. "The 

 words of the song refer to the person who is being 

 initiated. Many sick persons are initiated in order that 

 they may be restored to health. The Midc comprehends 

 health of body, mind, and spirit in one general idea." Ii 

 is somewhat unfortunate that this short memoir is simph 

 entitled " Chippewa Music," for on reading the title a non- 

 musical person might be led to overlook a piece of work 

 which, as we have seen, covers a much wider ground. 



As the result of two seasons' field work, Mr. Gerard 

 Fowke has published a memoir on the mounds near the 

 Missouri river, mainly between Gasonade River and 

 Moniteau Creek. The mounds were erected on narrow 

 ridges, with no regard to orientation; each contained a 

 vault witli sides sloping outwards, and composed of 

 irregular stones. They contained one or more skeletons, 

 either doubled up or disarticulated, the flesh having been 

 first removed ; in these cases the bones sometimes appear 

 to have been thrown carelessly jnto the vault. The bones 

 were in such a decayed and friable condition that very 

 few could be preserved or measured. Dr. A. Hrdlicka 

 states that most of the crania are of the dolichocephalic 

 Indian type, two or three being extreme forms in this 

 respect, suggesting similar specimens recovered in New 

 Jersey from the burials of the Delawares and also from 

 the mounds of the Illinois River. A large number of the 

 vaults are- figured, as well as objects found within them. 

 The author states that :— " As the Osage Indians never 

 ascended the Missouri farther north than the Osage River, 

 and as the stone vaults above thai point show progressively 

 more skill in their construction, we must attribute them 

 either to the Kansa Indians or to some tribe whose name 

 is now lost." A. C. HaddoN. 



RADIANT MATTER. 1 

 'Fill-, velocity with which helium is cast out by radio- 

 active bodies at the moment >ii change uik- con- 

 siderably from on., element to another. Thus ih,. radiant 

 atoms of radium C possess a far higher velocity than those 

 of uranium or ionium. This fact is apparent in the 

 greatei distance to which the a rays of tie- former will 

 penetrate in air or in any other substance. The distance 

 traversed in air is known as the "range." The follow- 

 ing table shows the ranges ol a rays from the various 

 known radio-active elements. Thus we see that whereas 

 the helium from radium C is projected nearly 7 centi- 

 that from uranium only reaches ?■- centimetres. 

 thorium series, one of the elements, thorium C, 

 a range of 8-6 centimetres. This is the longest 



Range in Air. 



metres 

 In the 

 .mains 

 known 



1 From a lecture delivered befote the Renal Dublin So, icty, 

 by Prof. I. J..|y. F.R.S. 



NO. 



February 3, 



87] 



706 

 483 

 423 



Thorium C 



Thorium X 



Thorium emanation 



Thorium B 



Radiothorium 



Thorium 



Actinium X 6-55 



Actinium emanation 5-S 



Actinium B 5-5 



Radioactinium 4-S 



By a most ingenious series of observations, Bragg has 

 revealed some unexpected and interesting features attend- 

 ing the ionisation effects of the a rays upon gases through 

 which they are projected. By measuring the amount of 

 ionisation effected at different points along the path of the 

 ray, Bragg and Kleeman have shown that at first, when 

 the velocity is greatest, the ionisation effected is least, and 

 that the amount of ionisation — that is, the number of ions 

 created — greatly increases just before the atom comes to 

 rest. 



Let the ray be supposed to move along the line AB — 

 this line representing the range. If at each point of its 





. of ai 



path we erect a perpendicular line proportional to the 

 number of ions , realed by the flying helium atom, then, 

 by joining up the ends "I these lines, we obtain the curve 

 shown. It will bi noticed that a very well-defined maxi- 

 mum exisiv, after which the ionisation rapidly drops to 

 nil. The curv, reproduced is due to Geiger, who has 

 added consideraldj 1,, ,,,,, knowledge ,,! the subject. 



Here is a small speck of the substance, pitchblende - 



the uranium ore 1 which radium is derived. All the 



elements of the uranium series are present. We are sure, 

 then, that every a raj proper to this series, the ranges of 

 which are given in the table, is being emitted by this 

 particle ol pitchblende. Let us form a mental picture of 

 what is going on around it.' 



Furthest out >d all, ih,' helium from radium C is pro- 

 jected. Ii .mains a distance of 7 centimetres. The 

 greater part by far of its ionisation i- done near the end 

 of iis flight. Hence, remembering that these rays are 

 darting radially in .,11 ,lir,, lions from lie piece ,if pitch- 

 blende, there is a shell of intense ionisation of spherical 

 form existing around this pitchblende, and at a distance 



1 This might, possibly, be realised by condensing water vapour upnn the 

 ions according lo the method described by C. T. R. Wilson (Proc. R. S., 

 June, ion). 



