136  Granular  Effervescent  Powders.     /Am- Jour- Pharm- 
March,  1891. 
mass  becomes  pasty.  This  pasty  portion  is  lifted  up,  at  intervals  of 
a  few  seconds,  to  the  top  so  as  to  allow  all  the  powder  to  come  into 
contact  with  the  bottom  of  the  granulating  tin  used.  It  is  then 
pressed  through  a  wire  sieve  of  convenient  sized  mesh.  The  granules 
are  received  on  white  paper  and  dried  in  a  warm  room  on  suitable 
trays.  By  this  method  we  have  no  S.V.R.  used,  neither  have  we  a 
superabundance  of  powder  mixed  with  our  granules.  Care,  of 
course,  must  be  taken  to  apply  a  certain  amount  of  heat  to  prevent 
too  great  a  loss  of  C02,  otherwise  our  product  would  be  deficient  in 
effervescence.  A  little  experience  in  manipulation  is  soon  obtained 
and  as  much  as  50  per  cent,  of  active  ingredients  can  readily  be 
incorporated.  The  B.P.  sodii  tart,  effervesc.  may  be  taken  as  a 
typical  example  of  the  medicaments.  I  need  not  go  over  the 
details  of  manufacture  again,  but  will  compare  it  with  that  popular 
article  which  seems  to  be  sold  cheaper  and  of  more  inferior  quality 
year  by  year.    I  refer  to  what  is  known  as  citrate  of  magnesia. 
Magnesia  in  this  preparation  is  frequently  entirely  absent,  and 
such  phrases  as  "  so-called  "  or  "  known  to  the  public  as,"  some- 
times omitted  altogether  from  the  labels.  The  same  maybe  bought 
of  grocers,  etc.,  outside  of  pharmacy,  nicely  flavored  with  lemon, 
vanilla,  etc.,  in  divers  colors.  As  an  example  of  what  pleases  the 
public,  the  following  is  the  composition  of  a  preparation  boldly 
styled  citrate  of  magnesia  : 
Acid,  tartaric,   37  parts. 
Sodii  bicarb. ,   41  Yz  parts. 
Sugar,   21  parts. 
Magnes.  sulph.  exsic,   part. 
The  above  compound,  sold  under  the  name  of  citrate  of  magnesia, 
was  not  even  in  granular  form,  but  retailed  under  that  name  and 
sold  in  the  simple  form  of  a  saline.  In  the  words  of  one  of  our 
weekly  journals,  "  Never  use  good  stuff  and  remain  careless  of 
details  in  the  struggle  for  existence." 
Two  prosecutions  occurred  about  a  year  ago  in  reference  to 
granular  effervescent  citrate  of  magnesia,  the  special  adulteration 
being  lead  to  the  extent  of  -37  grain  per  pound.  Scientific  evidence 
having  been  given  to  the  effect  that  commercial  citric  acid  invari- 
ably contained  a  minute  quantity  of  lead,  the  stipendiary  on  con- 
sideration dismissed  the  case,  but  without  allowing  costs. 
In  the  same  year  a  chemist  in  Greenock  was  prosecuted  under 
