Am.  jour^pharm.i    Acids  of  Gastric  and  Intestinal  Juices.  25 
retically  but  also  in  practice  it  yields  fallacious  results  in  other  albu- 
minous fluids,  such  as  the  blood,  transudations,  white  of  egg,  etc.  The 
reason  is  that  the  factor  must  be  multiplied  by  the  difference  in  the 
specific  gravities.  In  proteid  solutions  (other  than  albuminous  urine) 
this  difference  varies  from  0*0016  and  0*0128,  whilst  in  albuminous 
urine  this  difference  is  much  smaller,  varying  between  0*00012  and 
0*00200 ;  that  is,  in  the  former  case  the  difference  is  from  6  to  13  times 
greater  than  in  the  latter,  and  therefore  so  many  times  greater  will  be 
the  error  introduced  by  the  use  of  a  constant  factor.  In  the  case  of 
urine,  this  error  may  be  neglected. 
ON  THE  ACIDS  OF  GASTRIC  AND  INTESTINAL 
JUICES.1 
By  Dr.  Poulet. 
The  author's  method  of  obtaining  the  acid  principle  of  the  stomach 
and  intestine  consists  in  dialyzing  either  the  contents  of  the  stomach  or 
intestine  obtained  from  an  animal  in  full  gastric  or  intestinal  digestion, 
or  the  scrapings  of  the  gastric  or  intestinal  mucous  membrane.  After 
dialyzing  for  twenty-four  hours,  the  resulting  liquid  is  evaporated  at  a 
gentle  heat  down  to  about  thirty  grams,  and  then  treated  in  a  wine- 
glass with  sulphuric  acid.  In  the  case  of  the  stomach  of  the  pig  and 
man  hippuric  acid  in  abundance  crystallizes  out ;  in  that  of  all  car- 
nivorous animals,  tartaric  acid,  whilst  tartaric  acid  is  found  to  be  the 
acid  separated  from  the  intestine.  It  would  be  tedious  to  follow  the 
author  through  the  exposition  of  his  methods  and  results  at  any  length. 
His  conclusions  have  certainly  the  charm  of  novelty,  but  many  objec- 
tions present  themselves  to  his  method  as  a  means  of  obtaining  the  free 
acid  secreted  either  in  the  stomach  or  intestine.  It  will  be  sufficient 
to  give  his  conclusions  as  summarized,  and  to  refer  for  details  to  the 
original  paper. 
The  gastric  juice  of  omnivorous  adults,  and  notably  of  healthy  men, 
contains,  in  the  first  stage  of  digestion,  hippuric  acid  alone.  Towards 
the  end  of  the  digestive  act  a  mixture  of  hippuric  and  tartaric  acids  is 
found.    The  latter  is  alone  found  in  the  secretion  of  the  mucous  mem- 
1  "  Nouvelles  recherches  expdirimentales  sur  les  principes  acides  du  sue  gas- 
trique  et  sur  celui  du  sue  intestinal"  in  Archiv.  de  physiolog.  norm,  et  pathol,  Oct- 
1st,  1888  ;  abstract  reprinted  from  The  Medical  Chronicle,  December. 
