Am.  Jour.  Pharm. 
November,  1915. 
^Experiences  with  Salol-coating  of  Pills.  515 
tating  in  the  air  until  the  salol  has  solidified,  removing  the  pin  when 
sufficient  coat  has  been  taken  on,  and  then  closing  the  puncture  with 
a  drop  of  melted  salol.  Second,  the  method  in  which  the  pills  are 
placed  in  a  vessel  in  which  salol  has  been  melted,  and  the  vessel 
rotated  until  the  salol  congeals. 
The  second  method  is  the  plan  given  in  the  National  Formulary, 
The  first  method  does  not  appear  to  have  been  as  generally  used 
as  the  second.  It  is  very  much  more  tedious  to  stick  pins  into  the 
.pills,  dip  them  into  the  salol  and  rotate  a  number  of  pills  at  one 
time  than  to  place  the  pills,  all  at  once,  into  a  vessel  and  rotate  it. 
Besides  the  salol  sometimes  chips  off  when  the  pin  is  withdrawn 
and  the  sealing  produces  an  unevenness  of  coat  which  is  not  pleasing 
to  the  eye. 
The  second  method  is,  therefore,  much  less  tedious,  and  more 
rapid,  and  with  a  little  practice  gives  excellent  results  both  in  amount 
of  salol  applied  and  in  appearance  of  finished  pill. 
The  pills  which  were  most  frequently  ordered  to  be  salol-coated 
contained  silver  nitrate,  sometimes  with  extract  of  hyoscyamus, 
sometimes  with  opium.  The  mass  should  be  hard  in  order  to  get 
the  best  result.  It  is  also  desirable  to  have  pills  as  nearly  round 
as  possible.  The  usual  dusting  powders  can  be  applied,  and  while 
it  is  best  not  to  leave  more  of  this  adhering  than  is  necessary,  the 
slight  amount  which  may  be  needed  in  some  cases  is  not  objection- 
able. Size  of  pill  does  not  matter,  although  as  in  almost  all  pill 
work,  a  pill  of  one  grain  weight  is  easier  to  manipulate  than  a  smaller 
one. 
In  the  experiments  made,  mass  was  added  to  the  very  small  pills  ; 
powdered  licorice  root,  kaolin,  talc  and  confection  of  rose  were  all 
used  with  good  results. 
The  National  Formulary,  page  No.  122,  section  No,  2,  Enteric 
Pill-Coating,  paragraph  B,  Salol-coating,  reads  as  follows : 
"The  pills,  carefully  freed  from  dusting-powder,  are  dropped 
into  a  capsule  containing  enough  Salol  (approximately  0.06  gm. 
(1  grain)  to  every  0.19  gm.  (3  grains)  pill),  previously  melted  by 
the  heat  of  a  water-bath  and  allowed  to  cool  so  that  by  passing  the 
hand  along  the  bottom  of  the  dish  there  is  scarcely  any  warmth 
felt,  and  the  capsule  is  then  rotated  until  the  pills  are  coated  and 
the  salol  has  congealed.  This  process  is  repeated  twice,  each  time 
reducing  the  salol  about  one-half.  Finally,  a  finishing  coat  is  ap- 
plied by  using  only  sufficient  salol  to  coat  the  dish  when  melted ;  the 
