122 
Life-History  of  a  Doctrine. 
( Am.  -lour.  Phan 
I      March,  1903. 
substances  are  made  up  of  simpler  parts  all  of  which  are  alike."  I 
am  as  yet  unable  to  form  a  judgment  in  regard  to  the  value  of  the 
evidence  thus  presented,  but  my  confidence  in  J.  J.  Thomson  gives 
me  faith  in  the  thoughts  suggested  by  him.  As  I  understand  it, 
the  worst  that  can  be  done  for  chemistry  by  the  corpuscle  is  to 
change  the  atom  so  slowly  that  it  would  take  something  like  a  mil- 
lion years  to  enable  us  to  detect  the  change  by  the  balance.  Per- 
haps the  atomic  weights  of  the  elements,  or  of  some  of  them,  are 
undergoing  change.  Whether  in  the  course  of  geological  ages  the 
atoms  are  becoming  simpler  or  more  complex  is  a  question  that 
appears  idle  at  first,  and  yet  when  we  bear  in  mind  the  fact  that  the 
atoms  of  our  day  have  already  been  subjected  to  a  great  variety  of 
influences  for  ages  past,  and  that  the  atoms  that  we  know  are  com- 
paratively complex,  we  may  at  least  suspect  that  the  tendency  so  far 
is  toward  complexity.  But  here  we  are  face  to  face  with  a  problem 
far  beyond  our  powers — the  action  of  eons  upon  ions. 
Even  if  we  assume  the  corpuscle,  our  conception  is  still  material- 
istic, and  we  have  to  face  the  question,  What  is  matter  ?  That  is  a 
deep  question — one  of  the  deepest  that  can  be  asked.  It  is  not  diffi- 
cult to  show  that  all  definitions  of  matter  that  have  been  given  are 
totally  inadequate ;  to  show  that  matter  is  a  product  of  the  imagina- 
tion ;  that  we  know  matter  only  in  so  far  as  it  affects  the  senses,  and 
our  senses  are  affected  only  by  the  different  forms  of  energy.  By 
logic  we  can  easily,  with  Ostwald,  reach  the  conclusion  that  u  mat- 
ter and  energy  are  not  to  be  thought  of  as  distinct,  as,  for  example, 
body  and  soul."  We  cannot  help  agreeing  with  him  further  when 
he  says :  "  If  we  attempt  to  think  of  matter  as  separate  from  the 
various  forms  of  energy  nothing  is  left.  Matter  is,  in  fact,  nothing 
but  a  group  of  different  energies  in  space."  But  what  is  energy  ? 
This  question  would  have  been  promptly  referred  to  the  physicists 
by  the  older  chemists,  but  the  chemists  of  to.day  are  physical  chem- 
ists or  chemical  physicists,  and  they  grapple  with  such  questions 
without  reserve.  Perhaps  the  nearest  approach  to  an  answer  is  that 
of  Herz,  who,  according  to  Ostwald,  "  expressly  declines  to  see  any- 
thing in  the  electro-magnetic  theory  of  light  but  a  system  of  six 
differential  equations."  By  means  of  mathematics,  relations  may  be 
expressed  and  the  story  of  nature  told  in  a  way  that  is  clear  to  one 
who  understands  the  language,  and  perhaps  the  time  will  come 
when  men  will  have  a  complete  record  of  the  various  forms  of 
