258  Nitrogen  in  Gums. 
nitrogenous  substance.  Numerous  precipitates  were  obtained,  but 
in  every  case  the  precipitate  contained  both  gum  and  nitrogen  in 
apparently  the  same  proportion  as  before.  The  dry  powdered  gum 
was  heated  for  two  hours  at  temperatures  varying  from  ioo°  to  1600 
C,  and  tested  both  by  boiling  alone  and  with  acids,  but  no  separa- 
tion occurred. 
EXAMINATION  OF  OTHER  GUMS. 
A  number  of  the  following  samples  were  prepared  by  students 
and  kindly  furnished  by  Professor  Tschirch  from  his  collection.  The 
No. 
Gum  From. 
Prepared  By. 
Pyrrol 
Reaction. 
Ut 
mus 
Enzyme 
1 
Japanese  lac  
Stevens 
Very  strong 
Blue 
Immediately 
2 
Weak 
.< 
30-  60  minutes 
3 
"         select    .  . 
Medium 
15-  60  " 
4 
H 
8-  13 
5 
Asafoetida  
« 
Strong 
„ 
1-   4  " 
6 
"        select  . 
'■ 
» 
1-  4 
7 
8 
Oscar  Halbey 
Weak 
60-120  " 
60- 
9 
Knitl 
•• 
30- 
10 
Elemi  
Dr.  Saal 
Strong 
30  seconds— 12  minutes 
11 
Bergmann 
15-  minutes 
12 
Chickle  
Schereschewski 
Weak 
Inactive 
13 
Tragacanth,  white  .  . 
Stevens 
Medium 
14 
"          yellow  . 
15 
"  white 
Acids  prepared  from : 
16 
Halbey 
Medium 
17 
Knitl 
Weak 
18 
Stevens 
Medium 
19 
Strong 
20 
remainder  were  prepared  by  the  writer.  In  the  case  of  the  gum- 
resins  the  resin  was  removed  by  extracting  with  alcohol,  the  gum 
dissolved  in  water  and  precipitated  by  alcohol,  purified  by  repeated 
precipitation  and  dried  in  an  exsiccator.  The  acids  were  prepared  by 
the  same  method,  with  the  exception  that  the  solutions  were  acidu- 
lated with  hydrochloric  acid  each  time  before  precipitation,  and  the 
/Am.  Jour.  Pharm. 
\       June,  1905. 
