94 
Chemical  Notes. 
(Am.  Jour.  Pharnu 
\        Feb.,  189U. 
hydrochloric  acid  for  a  quarter  of  an  hour,  after  which  time  the 
acid  is  washed  out  and  the  muslin  carefully  dried.  The  cloth 
is  now  fitted  to  retain  the  iodine  vapors.  .  The  iodine,  finely 
pulverized,  is  spread  evenly  upon  both  sides  of  the  fabric, 
which  is  then  loosely  rolled  and  introduced  into  a  jar.  The 
latter  is  warmed  until  vapors  begin  to  arise,  when  it  is  sealed 
and  placed  in  a  water-bath  for  two  hours  at  21 2°  F.  On  cool- 
ing, the  muslin  is  put  away  in  glass  jars  for  use. — Re'pert.  de 
P/iar.,  Dec.  10,  1889. 
CHEMICAL  NOTES. 
By  Henry  C.  C.  Maisch,  Ph.G.,  Ph.D. 
Valence  of  Aluminium. — Nilson  and  Petterson,  in  their  latest 
publication  on  the  vapor  density  of  aluminium  chloride 
(Zeitschr.  fur  physik.  Chemie,  1889,  p.  206)  report  on  some 
experiments,  which  support  their  previous  investigation  and 
from  which  they  draw  the  following  conclusions  :  From  the 
boiling  point  aluminium  chloride  is  in  constant  dissociation 
until  above  8oo°  C.  the  state  of  a  perfect  gas  is  reached  when 
the  vapor  density  corresponds  to  the  formula  Al  Cl3,  which 
does  not  change  at  the  highest  temperature  obtainable.  This 
proves  without  any  doubt  that  aluminium  is  a  trivalent 
element. 
Alkaloidal  Reagents. — A.  L.  Brociner  {four.  Pharm.  Chim.y 
1889  (5)  20,  p.  390)  draws  attention  to  a  solution  of  1  gm. 
perrutheniate  or  rutheniate  of  potassium  in  20  cc.  very  pure 
concentrated  sulphuric  acid  (sp.  gr.  1*184)  as  a  reagent  for 
alkaloids.  Solanine,  with  a  drop  of  this  reagent,  in  a  few 
minutes  begins  to  assume  a  red  color,  after  about  20  minutes 
the  whole  liquid  has  acquired  the  same  color,  which  disap- 
pears on  slight  heating.  Ononin  is  colored  immediately 
brownish-red.  Chelidonine  gives  a  green  coloration.  Impera- 
torin,  at  first  blue,  soon  changes  to  an  intense  green.  The 
latter  reaction  is  best  obtained  with  the  perrutheniate,  while 
rutheniate  gives  the  best  results  with  the  rest.  The  author 
furthermore  calls  attention  to  a  solution  of  1  gm.  ammonium 
uranate  in  20  cc.  concentrated  sulphuric  acid.  This  solution 
must  be  prepared  just  before  using.    Codeine,  on  slight  heat- 
