io  Determination  of  Boric  Acid.      (A™ania?y  ^f7m' 
appears  and  all  suggestion  of  pink  or  orange  shade  has  disappeared. 
An  equal  volume  of  neutral  glycerin  was  then  added  and  the  titra- 
tion completed  to  the  appearance  of  a  pink  color  with  phenolphtha- 
lein. 
It  is  essential  that  care  should  be  taken  to  cool  the  solution  to 
room  temperature  before  neutralizing  as  the  indicators  change  color 
at  a  decidedly  different  hydrogen  ion  concentration  when  warm. 
It  will  be  seen  that  the  results  obtained  by  the  use  of  methyl 
orange  are  high,  while  those  obtained  in  the  titrations  in  which 
methyl  red  was  used,  with  one  exception,  are  very  close  to  the  theo- 
retical. 
Boric  acid 
taken. 
Sodium  carbo- 
nate taken. 
II3BO3  found 
methyl  orange. 
Error. 
H3BO3  found 
methyl  red. 
Error. 
0.2000  Gm. 
1.0  Gm. 
0.2003  Gm. 
+  0.15% 
0.1988  Gm. 
-.60% 
0.2000  " 
0.2038  " 
+  1-9% 
0.2004  " 
+  .20% 
0.2000  " 
0.2024  " 
+  1-2% 
0.2001  " 
+  .05% 
0.2000  " 
0.2034  " 
+  1-7% 
0.2500  " 
0.2523  " 
+  .92% 
0.2497  " 
-.12% 
0.2500  " 
0.2501  " 
+  .04% 
Average  ei 
1.17% 
0.10% 
Conclusions. 
The  results  seem  to  indicate  that  methyl  red  can  be  used  in  place 
of  methyl  orange  in  the  titration  of  boric  acid,  that  it  is  more  satis- 
factory since  a  sharp  endpoint  can  be  obtained,  and  that  more  ac- 
curate results  can  be  obtained. 
SOME  COLOR  REACTIONS  OBTAINED  FROM  THE  EX- 
TRACT OF  ACER  SPICATUM  (FALSE  VIBURNUM 
OPULUS,  VIBURNUM  OPULUS 
U.  S.  P.  VIII). 
By  B.  H.  St.  John. 
Contribution  from  the  Laboratory  of  the  American  Medical  Association, 
Chicago,  111. 
Some  two  years  since,  while  in  the  service  of  the  Bureau  of 
Chemistry,  the  author  was  engaged  in  the  examination  of  a  number 
of  patent  remedies  which  were  claimed  to  be  of  value  in  the  treat- 
