54 
IODIDE  OF  ALUMINUM. 
of  the  retort.  From  this  time  the  heat  must  be  kept  up  uni- 
formly, until  no  more  phosphorus  comes  over  ;  since,  if  the  heat 
is  allowed  to  decrease,  air  or  water  may  get  into  the  retort,  and 
give  rise  to  explosions.  During  the  distillation,  the  water  in 
the  receiver  is  kept  cold,  and  the  phosphorus  is  removed  from 
time  to  time  by  an  iron  ladle ;  so  that  in  the  event  of  an  explo- 
sion, phosphorus  may  not  be  ignited  and  thrown  about. 
For  obtaining  the  phosphorus  in  the  shape  of  sticks,  the  ordi- 
nary vessel  is  used  for  melting  the  phosphorus  ;  but  in  the  cock 
is  cemented  a  glass  tube,  several  feet  long,  and  of  uniform  bore. 
This  is  closed  at  the  lower  end  with  a  cork,  to  which  a  wire  is 
attached,  and  the  glass  tube  is  surrounded  by  a  vessel  containing 
cold  water.  The  cock  of  the  vessel  containing  the  melted  phos- 
phorus is  then  opened,  so  as  to  admit  the  phosphorus  into  the 
glass  tube,  and  when  it  has  solidified,  the  cork  is  carefully  with- 
drawn, and  with  it  the  rod  of  phosphorus,  while  fresh  liquid 
phosphorus  passes  into  the  tube.  By  a  little  management  the 
whole  of  the  phosphorus  may  thus  be  drawn  out  in  one  stick, 
and  coiled  round  in  the  tube,  or  cut  with  scissors  under  water.  If 
the  stick  should  happen  to  be  drawn  out  too  quick,  before  the 
phosphorus  in  the  tube  is  solidified,  the  cock  must  be  shut,  the 
phosphorus  that  escapes  put  back  into  the  melting  vessel,  and 
the  operation  recommenced  as  in  the  first  instance. — London 
Pharm.  Journal. 
ON  IODIDE  OF  ALUMINUM. 
By  E.  Weber. 
Wohler  has  shown  that  iodide  of  aluminium  cannot  be  prepared 
by  the  same  method  which  Oerstedt  in  1820  obtained  the  chlo- 
ride, and  Lowig  subsequently  the  bromide  of  aluminum,  namely, 
by  mixing  alumina  with  charcoal  and  igniting  the  mixture  in  a 
current  of  chlorine  or  bromine. 
By  treating  metallic  aluminum  with  iodine,,  the  author  has 
obtained  iodide  of  aluminum,  Al2  I3.  Some  filings  of  aluminum 
were  placed  in  a  glass  tube  about  7  centimetres  in  length  closed 
at  one  end ;  dry  iodine  was  then  put  in  and  the  tube  sealed  with 
the  lamp.  It  is  advisable  to  employ  1  part  of  aluminum  to  10-11 
