Am.  Jour.  Pharni.  ) 
October,  1909.  / 
Assay  of  Heart  Tonics. 
463 
of  an  average  preparation  of  a  given  drug.  Such  standard  may 
be  obtained  by  mixing  equal  parts  of  not  less  than  ten  lots  of  the 
finished  preparation,  derived  from  the  same  number  of  lots  of  crude 
drug  which  have  been  determined  to  be  of  first-class  quality  by 
physical  and  botanical  examination. 
9.  The  action  of  the  drug  being  assayed  should,  if  possible,  be 
compared  with  the  action  of  the  standard  upon  the  same  animal. 
10.  Tn  those  cases  where  it  is  impossible  to  make  an  assay  using 
TABLE  I. 
OUTLINE  OF  METHOD  OF  OBTAINING  M.F.D.  TINCTURE  STROPHANTHUS,  U.  S.  P.  l8gO. 
Dose  per  Grn. 
Total  dose 
Weight. 
body  weight. 
1%  sol. 
Result. 
16  Gins. 
.0001 
.16 
Alive. 
15  " 
.00015 
•23 
Alive. 
17  " 
.0002 
-  .34 
Alive. 
15  " 
.00025 
.38 
Dead. 
16  " 
.0002 
•32 
Alive. 
17  " 
.00021 
.36 
Alive. 
15  " 
.00022 
•33 
Dead. 
16  " 
.00023 
■37 
Dead. 
17  " 
.00024 
41 
Dead. 
16  " 
.00022 
•35 
Dead. 
17  " 
.00022 
■37 
Dead. 
15  " 
.00022 
•33 
Dead. 
16  " 
.00022 
•35 
Alive. 
17  " 
.00022 
•37 
Alive. 
STANDARD. 
16  " 
.00016 
.26 
Alive. 
16  " 
.00016 
.26 
Dead. 
16  " 
.00016 
.26 
Dead. 
17  " 
.00016 
.27 
Dead. 
18  " 
.00016 
.28 
Alive. 
.00016  16 
Strength  of  sample  is  =  —  of  the  standard  —  72  per  cent  =  465  + 
.00022  22 
heart  tonic  units  (H.  T.  U.s)  per  Cc. 
a  single  animal,  a  sufficient  number  of  animals  of  as  nearly  uniform 
resistance  as  possible  should  be  employed  to  rule  out  any  individual 
idiosyncrasy.  In  the  testing  of  the  heart  tonics  upon  frogs,  this  is 
of  great  importance. 
11.  Apparatus  required  for  making  assays  of  the  heart  tonics. 
Small  wire  frog  baskets  with  legs  and  covers  or  frog  glasses  and 
plates  will  do,  care  being  taken  not  to  set  the  baskets  too  deeply  in 
water  and  not  to  fill  the  plates  sufficiently  full  of  water  to  drown  the 
