TRANSFORMATIONS  OF  PROTOCHLORIDE  OF  MERCURY.  171 
oxide  of  iron,  it  blackened  this  oxide,  the  water  lost  its  sulphu- 
rous properties,  and  the  black  sulphuret  treated  with  hydrochloric 
acid  disengaged  hydrosulphuric  acid,  leaving  very  finely  divided 
sulphur  undissolved. 
I  proved,  besides,  that  the  sand  of  the  black  mud,  after  hav- 
ing been  washed  with  boiling  water,  and  freed  from  all  sulphuret 
of  calcium,  was  colored  by  protosulphuret  of  iron,  "which  disen- 
gaged hydrosulphuric  acid  when  it  was  treated  with  hydrochloric 
acid. — Chemist,  Sept.,  from  Comptes  Rendus,  July  21,  1856. 
ON  THE  TRANSFORMATIONS  WHICH  PROTOCHLORIDE  OF  MER- 
CURY UNDERGOES  UNDER  THE  INFLUENCE  OF  WATER,  ALCO- 
HOL AND  HEAT. 
By  M.  Berthe. 
In  this  memoir  the  author  arrives  at  the  following  conclu- 
sions : — 
1.  That  under  the  influence  of  an  elevation  of  temperature, 
and  especially  in  contact  with  alcohol  and  water,  the  protochlo- 
ride  of  mercury  is  decomposed,  and  gives  rise  to  a  certain  quan- 
tity of  bichloride. 
2.  That  Smithson's  battery,  put  in  contact  with  calomel  in 
suspension  in  water,  gives  rise  to  the  same  reaction,  and  that 
consequently,  whenever  we  wish  to  free  calomel  from  the  bichlo- 
ride which  it  may  contain,  or  to  detect  the  presence  of  this  salt 
in  it,  we  should  employ  the  liquids,  water,  alcohol,  or  ether, 
only  at  the  ordinary  temperature  ;  and  that  before  resorting  to 
the  use  of  Smithson's  battery,  we  should  make  sure  of  the 
perfect  limpidness  of  the  liquor. 
3.  Finally,  in  a  physiological  point  of  view,  it  maybe  deduced 
from  these  experiments  that  if  a  continued  temperature  of  40° 
to  50°  C.  (104°  to  122Q  F.)  is  sufficient  for  causing  the  partial 
conversion  of  the  protochloride  of  mercury  into  bichloride,  it 
seems  scarcely  doubtful  that  this  conversion  is  so  much  the  more 
likely  to  be  produced  in  the  organism,  when  it  is  subjected  to  a 
temperature  approaching  that  necessary  for  the  transformation 
in  presence  of  a  relatively  considerable  quantity  of  alkaline 
chlorides.  This  is  an  additional  proof  in  support  of  the  opinion 
expressed  by  M.  Mialhe,  relative  to  the  mode  of  action  of  this 
compound.— Chemist.  Sept.,  from  Comptes  Rendus,  July  21, 1856, 
