78  MANUFACTURING  PRUSSIATE  OF  POTASH. 
paration  of  it,  symptoms  which  were  new  to  him,  and  amongst 
them,  a  remarkable  feeling  of  weariness.  Its  presence  in  the 
body  is  readily  shown.  A  portion  of  any  part  of  the  body  poi- 
soned by  it,  not  bigger  than  a  pea,  is  enough  for  the  analyst. 
Its  presence  will  be  instantly  disclosed  by  spectral  analysis. 
We  shall  hear  more  of  this,  no  doubt ;  for  M.  Lamy  has  pre- 
sented M.  Bernard  with  a  quantity  of  thallium  for  experiment — 
the  society  for  the  protection  of  animals  notwithstanding.  We 
need  hardly  add,  that  thallium  will  be  rapidly  introduced  into 
the  practice  of  medicine.  We  shall  now  every  day  expect  the 
announcement  from  some  confrere  of  the  wonderful  "  effects  of 
thallium  "  in  epilepsy  or  some  other  like  incurable  disease,  with, 
of  course,  a  list  of  cases  distinctly  illustrative  of  the  statements 
and  belief  of  the  author  Med.  News  and  Library,  Dec, 
1863,  from  Brit.  Med.  Jour.,  Sept.  12,  1863. 
KESULTS  OF  AN  EXAMINATION  OF  THE  PEOCESS  FOR 
MANUFACTURING  PRUSSIATE  OF  POTASH. 
By  the  late  Mr.  John  Lee,  and  Dr.  Richardson. 
These  experiments  were  made  as  far  back  as  1847,  but  the 
notes  had  been  overlooked,  and  were  only  found  when  it  became 
necessary  to  prepare  an  account  of  the  manufacture  of  this  salt 
for  the  new  edition  of  the  Chemical  Technology. 
The  experiments  were  made  in  gun-barrels,  and  the  same 
mixture  of  materials  was  employed  in  each  case.  Clean  horn, 
carefully  rasped,  was  mixed  with  the  best  potashes  and  iron 
filings.  A  small  quantity  of  water  was  added,  to  assist  in  making 
an  intimate^ mixture,  which  was  carefully  dried  and  reduced  to  a 
fine  powder.    This  mixture  was  composed  of, — 
Horn,  .....  1600 
Potashes,  .....  17-72 
Iron,      x  .  .  .  .  .  3-00 
Moisture,       .  .  .  .  .3-28 
4000 
A  potash-charcoal  was  made  by  soaking  13  parts  of  wood- 
charcoal  with  a  solution  of  4  parts  of  potashes,  and  then  per- 
fectly dried. 
