It  had  been  noticed  that  when  niton  was
allowed  to  act  on  water,  not  only  were  oxygen  and
hydrogen  formed  in  abundance,  apparently  from
the  decomposition  of  the  water  ;  but  also  that
helium  and  neon  were  present.  Objection  was
taken  to  the  conclusion  drawn  from  these  experi-
ments ;  namely,  that  in  presence  of  water,  neon  is
one  of  the  products  of  the  disintegration  of  niton.
It  was  stated,  and  with  justice,  that  it  is  possible
to  detect  neon  in  less  than  0*5  cubic  centimetre  of
air,  if  proper  precautions  be  taken.  Attention  was
again  directed  to  this  matter,  when  it  was  dis-
covered, in  course  of  the  analysis  of  the  gases
escaping  from  the  King's  Well  at  Bath,  that  while
the  argon  present  in  these  gases  amounted  to  only
three-quarters  of  that  present  in  an  equal  volume
of  air,  the  volume  of  the  helium  was  sixty  times,
and  that  of  the  neon  one  hundred  and  eighty
times  as  great  as  those  normally  present  in  air.
