536  Estimation  of  Citric  Acid  hy  Baryta.  {^^r>ic^i^im^^' 
ON  THE  ESTIMATION  OF  CITRIC  ACID  BY  BARYTA. 
Editor  American  Journal  of  Pharmacy  : 
Dear  Sir. — As  you  published  in  the  Nov.  number  of  the  American 
Journal  of  Pharmacy,  an  article  of  Mr.  H.  Kiimmerer  on  the  Deter- 
mination of  Citric  Acid,  I  take  the  liberty  to  present  you  my  claims 
for  priority  on  the  subject.  In  June,  1871,  the  American  Chemist 
published  an  essay  of  mine  on  Citric  Acid  and  Citrates,  which  covers 
the  whole  ground.  I  enclose  a  reprint  of  that  article  very  slightly 
modified. 
Aside  of  this,  several  of  Mr.  Kammerer's  statements  do  not  agree 
with  my  observations.  For  instance,  he  states  that  citrate  of  baryta  is 
insoluble  in  water  ;  my  experiments,  repeated  a  number  of  times, 
showed  plainly  the  contrary.  He  says  also  that  the  presence  of  vege- 
table  acids  does  not  interfere  w^th  the  reaction,  while  I  have  observed 
that  free  acetic  acid  causes  water  to  dissolve  quite  a  large  percentage 
of  citrate  of  baryta. 
1  will  leave  to  analytical  chemists  to  decide  on  the  availability  for 
analysis  of  the  compound  proposed  by  Mr.  K.,  which,  he  admits  him- 
self, contains  sometimes  4,  sometimes  7  equivalents  of  water. 
For  my  part,  I  found  precipitated  citrate  of  baryta  highly  hygrome- 
tric,  and  for  that  reason  proposed  to  always  transform  it  into  sulphate 
for  exact  determination. 
The  analytical  part  of  my  paper  may  not  interest  pharmacists, 
but  you  will  see  that  I  describe  and  publish  the  mode  of  preparing 
^hree  new  soluble  combinations  of  citrate  of  bismuth,  all  more  stable 
than  the  officinal  salt.  I  mention  also  quite  a  new  class  of  ferrugi- 
nous compounds,  such  as  soluble  phosphate,  hypophosphite,  valeria- 
nate and  arseniate  of  iron,  which  cannot  fail  to  interest  our  profession. 
Before  closing,  I  would  ask  your  kindness  to  insert  in  one  of 
your  next  issues  the  following  correction  to  a  paper  you  published  in 
April,  1871.  On  page  169,  the  third  line  from  the  bottom  of  page, 
instead  of  chlorate  of  potassa  348  grains,  it  should  be  chlorate  of  po- 
tassa  425  grains. 
Yours  respectfully, 
J.  Creuse. 
Brooklyn,  Nov.  17,  1871 
