PHARMACEUTICAL  GLEANINGS  AND  NOTICES. 
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various  ways  to  coat  pills  in  the  forty-five  experiments,  and  a 
record  retained  of  their  condition  after  two  months  keeping  in 
a  dry  place,  and  then  of  the  effect  produced  by  transfer  to  a 
damp  cellar,  by  dipping  in  cold  water,  and  of  the  length  of 
time  warm  water  at  90v  required  to  soften  and  dissolve  the 
core.    The  last  form  of  trial  was  with  but  a  limited  number. 
The  author  in  summing  up  his  conclusions  says  :  «  These 
experiments  show  that  the  oft-repeated  story  about  silvered  pills 
being  difficult  of  solution,  must  be  looked  upon  as  a  popular 
error.  The  reason  why  pills  occasionally  pass  through  the 
stomach  undigested,  must  be  sought  for  either  in  the  state  of 
the  patient,  or  the  composition  of  the  pill,  rather  than  to  the 
nature  of  its  coating;  for  even  the  dipping  in  lac  varnish  did 
not  protect  the  pill  formore  than  an  hour,  whilst  in  the  stomach 
heat  and  moisture  are  assisted  by  chemical  and  mechanical 
means."  "Most  of  the  formulae  yield  coatings  which  are  effec- 
tual in  covering  the  taste  of  the  pills  for  a  sufficient  time. 
As  far  as  my  experiments  have  gone,  none  of  the  coatings 
cover  the  odor  of  pills  of  assafoetida,  camphor,  &c." 
Of  the  various  processes,  the  easiest  are  those  in  which  the 
pills  are  first  rolled  in  water  or  varnish,  and  then  in  a  powder ; 
viscid  fluids  like  albumen  and  mucilage  are  more  troublesome. 
The  author  prefers  a  mixture  of  spirit  and  water  for  aqueous, 
and  lac  varnish  for  resinous  liquids.  Of  the  powders,  magnesia, 
lycopodium  and  sugar  are  apt  to  become  clotty  ;  sugar  gives  a 
granular,  rasp-like  surface;  French  chalk  readily  produces  a 
smooth  uniform  coat  with  many  of  the  fluids,  but  is  improved 
by  the  addition  of  resin  when  the  liquid  used  is  alcoholic  ;  traga- 
canth  is  apt  to  produce  a  rough  granular  coating.  The  author, 
who  esteems  the  power  of  resisting  moisture  a  very  important 
condition  of  success,  says  the  disadvantage  of  using  coatings 
soluble  in  water  will  be  seen  by  the  readiness  with  which  many 
of  the  pills  become  adhesive  when  exposed  in  a  damp  situation. 
The  addition  of  sugar  to  tragacanth  increases  its  tendency  to  soften. 
He  also  finds  Mr.  Furley's  coating  (albumen  with  tragacanth 
and  sugar)  to  become  speedily  clammy  in  certain  cases,  as 
where  pills  contain  muriate  of  ammonia  or  glycerin.  The 
author  concludes  with  the  following  paragraph  :    Probably  the 
