RUBIDIUM  IN  VEGETABLE  SUBSTANCES,  ETC. 
441 
proving  the  great  dissemination  of  rubidium  in  nature.  Having 
found  the  new  metal  in  the  salts  from  beet-root,  which  it  is 
known  are  very  rich  in  potash,  it  seemed  of  interest  to  seek  for 
it  in  other  vegetable  substances,  which,  by  the  readiness  with 
which  they  remove  potash  salts  from  the  soil,  more  or  less  ap- 
proach beet-root  in  this  respect.  I  will  confine  myself  in  this 
extract  to  point  out  the  analytical  results  which  I  have  ob- 
tained, omitting  the  methods  of  separation  and  analysis  given 
in  my  memoir. 
1.  Tobacco. — I  have  at  present  only  examined  the  leaves  from 
Kentucky  and  Havanna.  M.  Schlesing,  Directeur  de  l'Ecole 
d'Application  des  Tabacs,  has  been  good  enough  to  evaporate  to 
dryness  in  his  laboratory  a  certain  quantity  of  water  which  had 
been  used  for  the  prolonged  washing  of  Kentucky  leaves.  The 
ignited  residue  was  tolerably  white,  spongy,  and  very  rich  in 
potash.  On  spectral  analysis  this  residue  gave  the  character- 
istic lines  of  lime,  lithium,  potassium,  and  rubidium.  The 
quantity  of  lithia  was  very  slight.  There  was,  on  the  other  hand, 
a  notable  quantity  of  rubidium. 
Leaves  from  Havanna,  best  quality,  were  carefully  burnt ; 
their  ashes  gave  me  on  analysis  results  identical  with  those  ob- 
tained from  the  Kentucky  leaves, 
2.  Coffee  and  Tea. — Coffee  and  tea  completely  and  carefully 
incinerated  left  ashes  rich  in  potash.  An  examination  of  these 
ashes,  after  appropriate  treatment,  showed  in  each  of  these  pro- 
ducts considerable  quantities  of  rubidium,  but  not  a  trace  of 
lithium.     Coffee  is  much  richer  in  rubidium  than  tobacco. 
•3.  Grapes  (crude  tarlary — M.  Kestner,  of  Thaun,  has  kindly 
sent  me,  at  my  request,  some  mother-liquors  obtained  in  the 
treatment  of  crude  tartars.  These  liquids  were  freed  from 
organic  matters  and  foreign  substances  which  they  contained, 
and  the  residues  then  submitted  to  spectral  analysis.  I  am  able 
to  state  definitely  that  they  contain  rubidium,  but  in  very  small 
quantity. 
It  appears  certain  from  these  facts  that  rubidium  is  one  of 
the  most  widely  distributed  simple  bodies  in  nature.  The  most 
different  vegetable  bodies  from  the  most  distant  localities  remove 
it  from  the  soil.  Moreover,  it  is  evident  from  my  researches 
that  the  presence  of  rubidium  is  not  necessarily  allied  with  that 
