AmMa^ss6arm"}  Pharmaceutical  Notes  from  Purdue  University.  233 
Chemical  Works)  required  43  c.  c.  of  the  zinc  solution,  and,  there- 
fore, contained  43  per  cent,  of  sulphide. 
The  following  experiments  in  the  preparation  of  calcium  sul- 
phide were  interrupted  by  the  close  of  the  term.  Two  specimens 
were  prepared  (as  directed  in  the  Pharmacopoeia)  by  mixing  90  gm. 
of  sulphur  with  100  gm.  of  lime,  and  heating  to  low  redness  in  a 
crucible  with  the  lid  luted  on.  0.36  gm.  of  each  product,  after 
treatment  with  ammonia,  required  16  and  18  c.  c.  standard  zinc  solu- 
tion respectively,  indicating  16  and  18  per  cent,  of  CaS.  The  lime 
was  not  perfectly  fresh  and  it  is  probable  that  sulphur  escaped  with 
moisture  or  carbonic  acid ;  yet  the  product  satisfied  the  test  as  de- 
scribed in  the  Pharmacopoeia. 
An  attempt  was  then  made  to  reduce  sulphate  of  calcium  by  ignit- 
ing two  hours  at  a  low  red  heat  in  a  current  of  coal  gas.  The  pro- 
duct was  darkened  by  the  separation  of  carbon,  and  contained  26  per 
cent,  of  sulphide. 
A  fourth  preparation  was  made  in  like  manner,  substituting  hydro- 
gen for  coal  gas  to  avoid  the  deposit  of  carbon.  After  two  hours' 
ignition,  this  contained  less  than  0*2  per  cent,  of  sulphide ;  after 
three  hours  further  ignition  in  hydrogen,  it  contained  only  2  per 
cent.  CaS. 
Unfortunately,  there  was  no  time  for  further  experiments  with 
various  reducing  agents  and  temperatures;1  and  these  experiments 
are  recorded  to  indicate  further  lines  of  investigation. 
VI.    Chloral. — by  b.  d.  westenfelder. 
Four  samples  of  commercial  chloral  hydrate  were  examined.  Be- 
sides several  tests  prescribed  in  the  Pharmacopoeia,  one  gram  of  each 
was  decomposed  by  caustic  soda,  the  excess  of  alkali  being  after- 
1 T.  S.  Dyinond  prepared  a  sample  of  light  pink  color,  containing  58  per  cent. 
CaS,  by  igniting  7  parts  of  sulphate  of  calcium  with  1  part  of  powdered  wood 
charcoal,  as  directed  in  the  British  Pharmac3pceia.  See  American  Druggist, 
xiii,  208  (Nov.  1884).  Should  there  be  any  reason  to  suppose  that  the  medi- 
cinal value  is  due  to  any  other  ingredient  than  the  monosulphide  (as  the 
editor  of  the  American  Druggist  believes),  this  fact  must  be  duly  considered. 
Preliminary  experiments  were  made  by  Mr.  Jay  upon  specimens  of  ammo- 
nium sulphide  which  had  undergone  changes  with  age,  and  probably  con- 
tained some  thiosulphate  as  well  as  polysulphides.  With  such  a  mixture  the 
three  volumetric  methods  gave  widely  discordant  results;  but  a  combination 
of  all  may  be  useful  in  distinguishing  the  several  ingredients  of  sulphuretted 
compounds.  R.  B.  W. 
