346  Note  on  Chloral  Hydrate.  {^"''KuTi^m^' 
solution  reddened  blue  litmus  slightly,  but  was  unaffected  by  nitrate 
of  silver.  Lieben's  test  gave  but  the  slightest  trace  of  iodoform.  On 
considering  all  the  above  reactions,  I  am  of  the  opinion  that  the  sam- 
ple under  examination  might  have  been  pure  hydrate  of  chloral  at 
first,  and  been  decomposed  by  standing ;  whether  this  is  true  or  not 
cannot  now  be  told. 
Since  commencing  the  above  experiments,  I  have  received  the  June 
number  of  the  American  Qhemist^  and  in  it  noticed  Dr.  Isidor  Walz's 
article  "  On  The  Reaction  of  Chloral  Hydrate  and  Sulphide  of  Am- 
monium," which  led  me  to  repeat  his  experiments  on  the  sample  I 
had  in  hand.  A  solution  was  made  with  distilled  water ;  this  was  ren- 
dered slightly  amraoniacal,  and  some  yellow  sulphide  of  ammonium 
(which  had  been  in  the  laboratory  about  a  year)  added.  The  liquid 
became  light  brown,  then  crimson  and  lastly  reddish  brown.  It  de- 
posited a  precipitate,  which,  after  washing  and  drying,  was  of  a  dirty 
yellow  color.  This  powder  was  dissolved  by  concentrated  sulphuric 
acid,  but  deposited  again  on  dilution  with  water.  Concentrated  ni- 
tric acid  oxidized  it  rapidly,  but  I  could  discern  no  volatile  compound 
formed  during  the  reaction.  Chloroform  and  alcohol  dissolve  it 
partially,  depositing  it  as  a  light  yellow  mass  on  evaporation.  Heated 
in  a  porcelain  crucible  it  gave  off  a  thick  yellow  oil,  of  a  disagreeable 
odor,  and  left  a  porous  coal.  Turpentine  dissolved  it  but  slightly,  if 
at  all. 
I  next  took  some  freshly  prepared  protosulphide  of  ammonium,  and 
added  it  to  an  aqueous  solution  of  the  chloral  hydrate  rendered  am- 
moniacal  as  before.  The  liquid  became  first  brown  and  then  dark  reddish 
brown,  depositing  a  precipitate  which  was  not  as  abundant  as  in  the 
former  reaction.  The  precipitate,  when  washed  and  dried,  formed  a 
powder  of  a  dirty  brown  color.  Its  chemical  properties  were  the  same 
as  those  of  the  yellow  substance  obtained  in  the  first  reaction,  with  these 
exceptions:  It  was  not  oxidized  as  rapidly  by  nitric  acid;  the  oil 
obtained  by  heating  it  had  a  more  penetrating  odor  ;  its  chloroformic 
solution,  when  evaporated,  left  a  light  brown  resinous  mass.  From  this 
we  may  conclude,  that  the  two  precipitates  are  similar,  if  not  identical. 
Dr.  Walz  suggests  that  persons  having  occasion  to  test  chloral 
hydrate  try  the  reaction  with  sulphide  of  ammonium,  as  by  comparing 
the  deportment  with  different  samples,  we  may  determine  its  value 
as  a  test  for  the  purity  of  this  substance. 
Battle  Creek,  Mich.,  July  11th,  1871. 
