508 
NEW  FORMULA  FOR  SYRUP  OF  CITRIC  ACID. 
ing  dish  and  oxidized  with  nitric  acid,  and  reduced  by  means  of 
sulphurous  acid  to  arsenious  acid,  and  precipitated  in  the  form 
of  AsSg,  by  means  of  sulphydric  acid ;  the  precipitate  digested 
with  ammonia,  in  order  to  free  it  from  the  small  amount  of  sul- 
phur present,  the  solution  filtered  from  the  undissolved  matter, 
and  evaporated,  dried  and  weighed,  and  found  to  weigh  15 
grains,  or  nearly  one  gramme. 
Louisville^  Oct.  6,  1870. 
ON  SULPHO-OARBOLATE  OF  ZINO. 
By  a.  B.  Lyons,  M.  D. 
Editor  Amer.  Journ.  Pharmacy  : 
Bear  iS'/r,— Having  had  occasion  several  times  to  prepare  zinc 
sulphocarbolate,  I  have  adopted  the  following  process  as  simple, 
economical,  and  in  every  respect  satisfactory.  A  crude  sulpho- 
carbolic  acid  is  first  prepared  in  the  usual  way,  by  heating 
together  sulphuric  and  carbolic  acids — seventeen  parts  of  the 
former  to  sixteen  of  the  latter.  This  is  diluted  with  ten  times 
its  volume  of  water,  and  saturated  with  carbonate  of  lead.  Into 
the  filtered  solution  of  sulphocarbolate  of  lead  is  introduced  a 
quantity  of  pure  granulated  zinc  equal  in  weight  to  the  carbolic 
acid  employed.  At  the  end  of  twenty-four  hours  the  solution 
will  usually  be  found  free  from  lead,  giving  no  precipitate  with 
sulphuric  acid  or  potassium  iodide.  When  quite  freed  from  lead, 
as  indicated  by  these  tests,  the  solution  is  decanted,  heated  to 
boiling,  filtered,  and  evaporated  to  a  small  bulk  to  crystallize ; 
or  the  evaporation  is  carried  to  complete  dryness,  the  salt  being 
obtained  in  the  granular  form.  The  salt  procured  in  this  way 
is  of  necessity  free  from  sulphate,  and  yields  fine  large  colorless 
crystals  without  any  empyreumatic  odor. 
Detroit,  Mich.,  Oct.  11,  1870. 
NEW  FORMULA  FOR  SYRUP  OF  CITRIC  ACID. 
By  Benj.  Lillard,  Nashville,  Tenn. 
This  syrup,  as  prepared  in  accordance  with  our  National  Phar- 
macopoeia, does  not  always  (even  when  combined  with  skilful 
