Am.  Jour.  Pharm, ) 
Sept, 1885.  j 
Sodio-Bismuth  Tartrate  and  Pepsin. 
421 
compactly,  so  that  after  a  moderate  duration  of  repose  the  supernatant 
liquid  may  be  decanted  quite  free  from  sediment.  The  mucus  should 
be  kept  out  of  the  filter,  as  it  greatly  impedes  filtration.  A  solution 
of  pepsin  contaminated  with  mucus  becomes  more  malodorous  with 
age.  The  odor,  however,  does  not  possess  a  putrid  character,  neither 
does  it  resemble  in  intensity  and  obnoxiousness  the  perfectly  execrable 
stench  of  the  so-called  scale  pepsin.  The  odor  caused  by  the  presence 
of  mucus  seems  to  emanate  from  an  acid  l)ody.  Neutralization  of  the 
solution  extinguishes  the  odor  instantaneously  and  completely.  On 
the  slightest  acidulation  it  as  promptly  and  intensely  reappears.  Such 
a  pepsin  when  dry  is  also  immediately  deodorized  by  the  admixture  of 
subnitrate  of  bismuth. 
The  writer  believes  that  the  Pharmacopoeia  sliould  incorporate  a 
process  for  the  preparation  of  pepsin.  It  should  direct  the  washed 
membranes  to  be  extracted  with  a  large  volume  of  cold  acidulated 
water.  The  practically  clear  macerate  should  then  be  treated  with 
sodium  chloride  to  saturation.  The  precipitated  crude  pepsin  should 
then  be  collected,  pressed  into  thin  sheets,  and  dried  in  the  open  air. 
The  dried  residue  should  then  be  cut  into  shreds,  and  after  rinsing 
with  cold  water  be  treated  with  about  40  parts  of  water  containing  one 
part  of  diluted  chlorhydric  acid,  at  a  temperature  not  much  in  excess 
of  40°C.,  during  the  period  of  one  to  two  hours.  The  nearly  clear 
supernatant  liquor  is  then  mixed  with  a  relatively  large  volume  of  fil- 
tered saturated  solution  of  sodium  chloride.  The  reprecipitated  pepsin 
is  then  collected,  pressed,  mixed  with  some  lactose,  dried  in  the  open 
air,  powdered,  and  after  assay  mixed  with  lactose  or  either  saccharose, 
so  that  the  finished  article  contains  about  ten  per  cent,  of  real  pepsin. 
Whether  pepsin  has  or  has  not  any  medicinal  value  is,  in  a  phar- 
macinal  asj)ect,  of  no  consequence.  The  consideration  to  pharmacy  is, 
does  the  medical  system  call  for  such  goods,  and  can  the  articles  be 
furnished? 
A  mixture  of  dry  pepsin  and  subnitrate  of  bismuth  is  very  popular 
with  all  practitioners,  almost  without  exception.  In  consequence,  a 
liquid  form  became  desirable.  This  solution  was  then  compounded 
with  strychnine,  and  has  in  this  form,  as  an  elixir,  become  to  be  a 
great  sta[)le. 
It  appears  that  pepsin  enters  into  chemical  coml)iuation  with  various 
bismuth  salts,  some  of  the  compounds  being  soluble  and  others  insoluble. 
When  a  solution  of  ammonio-citrate  of  bismuth,  representing  1  gram 
