372        Commercial  Extracts  and  Resins  of  Jalap.  { A%{fgu^£7h8arm; 
acid,  in  the  same  manner  as  the  resins  from  the  extracts,  and  with 
like  results. 
To  insure  correctness,  each  of  the  operations  were  repeated  with 
fresh  portions  of  the  preparations.  The  quantitative  results  are  given 
in  the  following  tables,  samples  from  the  different  manufacturers  being 
designated  by  numbers,  as  follows  :  No.  I  being  from  a  New  York 
manufacturer,  while  2,  3  and  4  were  made  by  different  firms  in  Phila- 
delphia. Resin  No.  4  was  made  by  myself  by  the  process  of  the  U. 
S.  Pharmacopoeia. 
EXTRACTS 
contained 
1 
2 
3 
4 
per  cent. 
7*5 
24*0 
68-5 
per  cent. 
13-0 
24*5 
62*5 
per  cent. 
I3'4 
.Ola 
18  7 
67-9 
per  cent. 
117 
1 6*3 
72*0 
Water,  ..... 
R  s  s  1  n ,  .... 
Soluble  in  water, 
Soluble  in  both  alcohol  and  water,  . 
260 
27*0 
24*0 
190 
Resins  from  Extracts  soluble  in  ether,  . 
"       «          "     insoluble  " 
8-5 
915 
io-8 
89*2 
16*3 
837 
i47 
85-3 
RESINS 
1 
2 
3 
4 
Water,  ..... 
Soluble  in  water, 
trace 
4-0 
trace 
3*5 
2*3 
Soluble  in  ether, 
Insoluble  in  ether,  . 
93*5 
9  0 
9ro 
97 
9°'3 
5*3 
947 
The  behavior  of  the  resins  when  separated  by  ether  and  treated  with 
solution  of  potassa  and  dilute  hydrochloric  acid  was  considered  sufficient 
proof  of  purity,  the  difference  in  the  proportion  of  the  active  consti- 
tuents being,  no  doubt,  mainly  due  to  the  quality  of  the  drug  used,  and 
perhaps  in  part  to  the  manner  of  preparation.  It  will  be  seen  by  the 
foregoing  tables  that  this  difference  consists  chiefly  in  the  relative  pro- 
portion of  the  resin  contained  in  the  extracts,  and  it  is,  of  course,  upon 
the  resin  that  the  activity  of  the  extracts  chiefly  depends,  although  the 
portion  soluble  in  both  alcohol  and  water  has  been  proven  to  be  pos- 
