Am  Jour  Pharm. )     C liavacters  of  Extvact  of  Calabar  Bean.  195 
April,  1885.      j  J 
It  is  evident,  tlierefore,  that  if  we  have  an  extract  which  is  niiscible 
with  water,  that  extract  has  been  improperly  prepared. 
Recognizing  that  the  alkaloidal  content  of  the  extracts  afforded  the 
best  indication  of  their  value,  I  have  determined  the  percentage  of 
alkaloid  in  each  case.  For  this  purpose  a  weighed  quantity  of  extract 
was  treated  with  water  acidulated  with  acetic  acid  and  lead  acetate 
added  in  excess  to  precipitate  coloring  and  resinous  matter.  After 
filtration,  the  excess  of  lead  was  precipitated  with  sulphuretted  hydro- 
gen, and  the  liquid  boiled  and  filtered,  then  evaporated  to  dryness  and 
weighed — (call  this  Extractive").  The  residue  was  again  dissolved 
in  distilled  water  and  rendered  alkaline  with  ammonium  carbonate. 
This  was  shaken  with  chloroform,  the  latter  separated,  filtered,  and 
evaporated  to  dryness.  The  weight  being  that  of  alkaloid  present,  0*5 
gram  of  extract  was  used  in  each  case,  and  the  fi)l lowing  results  were 
obtained  : 
Extract 
A.  Extractive  
 0-21 
gram      42    per  cent. 
Alkaloid  
 0  025 
"     -    b  " 
Extract 
B.  Extractive  
 0-365 
"     ^73  " 
Alkaloid  
 0-013 
"     =  2-6 
Extract 
C.  Extractive  
 0-40 
"  =80 
Alkaloid  
 0-009 
"     =  1-8 
Extract 
D.  Extractive  
 0-432 
"     =  86-4 
Alkaloid  
 0-006 
=  1-2 
In  alkaloidal  value  the  official  extract  is  therefore  the  highest ;  but 
when  it  comes  to  the  question  which  is  the  best  menstruum,  it  will  be 
seen  that  rectified  si)irit  is  not  the  best.  In  fact,  the  official  extract 
contains  the  most  alkaloid,  because  it  contains  less  extractive  than  the 
others.  The  following  comparison  shows  the  relative  power  of  each 
menstruum : 
Exty^act  obtained  from  4  ounces  of  the  drug. 
Rectified  spirit  23*1  grains  showing  5  per  cent,  alkaloid,  content 
1'15'5  grains. 
Alcohol,  66  per  cent.,  79*8  grains  showing  2*6  per  cent,  alkaloid, 
content  2*074  grains. 
Alcohol,  58  per  cent.,  115*9  grains  showing  1*8  percent,  alkaloid, 
content  2*086  grains. 
Proof  spirit  165*3  grains  showing  1*2  per  cent,  alkaloid,  content 
1*983  grains. 
