Am.  Jour.  Pharm.  \ 
■  Sept.,  1881.  j 
Pi'eservation  of  the  Journal. 
465 
volume  of  water,  and  to  4  cc.  of  this  solution  are  added  2  cc.  of  a  3 
per  cent,  solution  of  iodine.  If  the  color  becomes  red -brown  the 
peptone  contains  glucose ;  in  this  case  alcohol  would  give  an  errone- 
ous result,  and  it  is  necessary  to  have  recourse  to  the  determination  of 
the  nitrogen,  the  result  multiplied  by  6*05  giving  the  weight  of  dried 
peptone. 
If  the  solution  of  peptone  does  not  show  gelatin  or  glucose,  alcohol 
may  be  employed  with  some  advantage  in  respect  to  celerity,  pro- 
vided that  the  following  conditions  be  exactly  followed :  Take  10 
grams  of  pepsin,  pour  into  it  with  agitation  100  grams  of  absolute 
alcohol,  and  then  add  50  grams  of  ether.  Allow  it  to  deposit  for 
three  hours,  decant  carefully  and  dry  the  precipitate  at  100°C.  on 
tared  paper.  Calculate  out  the  weight  found  to  100  grams  of  solu- 
tion and  add  5,  and  this  will  represent  the  quantity  of  dry  and  pure 
peptone  contained  in  a  given  weight  of  the  solution. 
The  peptone  may  further  contain  alcohol  and  glycerin,  but  these 
cannot  become  a  source  of  error  in  the  precipitation  of  ether-alcohol. 
If  it  be  desired  to  determine  and  separate  the  glycerin,  the  peptonic 
solution  is  evaporated  at  90°C.  in  a  flat  capsule  until  the  Aveight 
remains  constant;  the  residue  is  then  treated  with  4  parts  of  alcohol 
and  1  part  of  ether  immediately  added ;  the  ether-alcohol  is  filtered 
oif,  and  by  careful  evaporation  leaves  the  glycerin  nearly  pure.  The 
capsule  is  returned  to  the  stove  and  afterwards  weighed ;  the  differ- 
ence in  weight  represents  the  quantity  of  glycerin  removed  by  the 
2i\.co\\(j\.~ Repertoire  de  Pharmacie,  vol.  ix,  262;  Phar.  Jour,  and 
Trans.,  July  2,  1881,  pp.  8,  9. 
Preservation  of  the  Journal,— 
To  the  Editor  : 
I  lately  devised  a  plan  for  keeping  my  Journals  clean  and  handy 
which  may  interest  some  of  your  readers,  viz. :  Remove  the  inside 
ledge  or  strip  of  straw-board  from  capcine  plaster  boxes,  when  each 
box  will  hold  just  one  volume.  These  I  keep  on  a  shelf,  upright, 
with  the  year  marked  on  a  label  on  the  back.  Will  some  craftsman 
tell  us  an  equally  cheap  and  effective  means  of  preserving  the  "  Drug- 
gists' Circular  ?  Respectfully, 
Thos.  D.  McElhenie. 
30 
