[     292     ] 
XXIII.  Note  to  a  Electrical  Vibrations  and  the  Constitution 
of  the  Atom."     By  Lord  Kayleigh  *, 
I  FIND  that  the  remark  (p.  121)  that  solutions  such  as 
(12),  (15),  (19),  involving  a  factor  e+r  u  cannot  apply 
to  a  problem  where  the  disturbance  is  supposed  to  originate 
in  the  neighbourhood  of  the  sphere"'''  needs  qualification. 
That  the  solutions  as  they  stand  cannot  be  so  applied  may  be 
admitted ;  but  Profs.  Lamb  t  and  Love  %  have  shown  how  by 
limiting  them  suitably  they  may  be  made  to  express  the 
advance  of  waves  into  a  region  previously  undisturbed.  This 
is  a  matter  of  some  importance,  and  I  regret  that  I  overlooked 
the  memoirs  just  cited,  in  which  clear  explanations  are  given. 
XXIY.  The  Heating  Effects  produced  by  Rontgen  Rays  in 
different  Metals,  and  their  Relation  to  the  Question  of 
Change  in  the  Atom.  By  H.  A.  Bumstead,  Ph.D.,  Ass't. 
Professor  of  Physics.  Yale  University  §. 
rpHE  study  of  the  phenomena  of  radioactivity  during  the 
J.  past  five  or  six  years,  and,  in  particular,  the  brilliant 
series  of  experiments  and  deductions  which  Ave  owe  to 
Rutherford,  have  left  little  room  for  doubt  that  a  certain 
proportion  of  the  atoms  of  radioactive  elements  are 
continually  breaking  up,  and  that  the  constant  emission  of 
energy  by  these  bodies  is  a  result  of  this  atomic  disintegration. 
This  process  in  any  given  radioactive  body  appears  to  be 
going  on  at  a  fixed  and  definite  rate  which  is  characteristic 
of  the  particular  substance  studied  and  which  is  quite  un- 
influenced by  any  external  circumstances  whatever. 
Although  radioactive  substances  have  been  subjected  ta 
the  greatest  extremes  of  temperature  available  in  the 
laboratory,  and  to  great  variations  in  other  physical  and 
chemical  conditions,  no  certain  results  have  been  obtained 
(so  far  as  the  writer  is  aware)  which  point  to  any  corre- 
sponding change  in  the  rate  of  decay  of  the  substance.  In 
fact  the  process  of  atomic  disintegration  has  appeared  to  be 
quite  beyond  human  control  ||. 
*  Communicated  bv  the  Author. 
t  Proc.  Loud.  Math.  Soc.  vol.  xxxii.  p.  208  (1900). 
%  Proc.  Lond.  Math.  Soc.  vol.  ii.  p.  88  (1904) 
§  Communicated  by  Prof.  J.  J.  Thomson,  F.R.S. 
||  The  apparent  change  (due  to  high  temperature)  in  the  rate  of  decay 
of  radium-excited  activity,  discovered  by  Curie  and  Danne,  lias  been 
shown  to  be  due  to  the  fact  that  the  successive  products  of  radium 
volatilize   at   different   temperatures.         Cf.   Bronson,   Am.  Jour.  Sci 
Julv  1905. 
