Am.  Jour.  Pliann.  1 
May,  1892.  / 
Chemistry  of  Digestion. 
241 
of  the  sample,  and  from  two  to  three  days  for  each  experiment,  but 
I  have  no  doubt  the  time  could  be  shortened. 
It  is  not  advisable  to  raise  the  standard  of  purity  beyond  the 
possible  reach  of  manufacturers,  but  I  think  chloroform  intended 
for  anaesthetic  purposes  should  be  expected  to  stand  more  exacting 
tests  than  those  of  the  present  Pharmacopoeia. 
The  temperature  at  which  85  per  cent  of  each  sample  distilled 
over  were  noted  ;  the  average  range  of  the  finer  ones  was  1  65  0  C 
and  that  of  the  less  pure  2-04°  C  which  gives  a  difference  of  0-39° 
C.  in  favor  of  the  purer  preparations;  this  is  a  smail  difference,  and 
as  some  of  the  bad  samples  distilled  over  below  the  average  range 
of  the  finer  ones,  I  am  inclined  to  think  that  the  boiling  point  is 
not  of  much  value  for  detecting  impurity  in  commercial  chloroform. 
THE  CHEMISTRY  OF  DIGESTION  AND  OF  THE 
GASTRIC  JUICE. 
By  Hayens  and  Winter. 
The  work  of  these  authors,  who  have  introduced  some  modifica- 
tions in  the  method  of  testing  the  gastric  contents,  has  excited  a 
good  deal  of  attention  and  discussion.  It  may,  therefore  be  useful 
to  give  a  summary  of  it,  abstracted  from  L'  Union  Medicate,  Nos. 
I34»  x35  and  136.  They  use  the  following  method,  which  they 
believe  to  be  very  exact  in  its  results.  The  gastric  fluid  is  filtered 
and  then  divided  into  three  portions,  each  of  5  ccm.,  which  is  placed 
in  three  capsules,  a,  b,  c.  In  capsule  a  an  excess  of  carbonate  of 
sodium  is  introduced,  and  the  three  are  then  dried  in  a  water  bath: 
afterwards  a  is  carried  to  commencing  redness,  the  contents  being 
frequently  stirred,  and  the  heat  is  discontinued  when  there  are  no 
longer  any  points  of  ignition,  and  the  mass  becomes  sticky.  After 
cooling,  distilled  water  is  added,  and  a  little  pure  nitric  acid  in 
excess ;  it  is  then  boiled  to  drive  off  the  carbonic  acid,  and  a  slight 
excess  of  carbonate  of  soda  added  to  produce  slight  alkalescence,  so 
that  the  indicator  used  in  testing  may  react  more  sharply.  The 
precipitation  of  the  calcareous  salts  indicates  that  the  limit  is  attained. 
After  filtration  and  washing  the  residue  with  boiling  water,  the 
liquids  are  added  together  and  the  chlorine  is  estimated  by  decinor- 
mal  solution  of  nitrate  of  silver  (using  chromate  of  potassium  as  the 
