344 
Infusion  of  Digitalis. 
Am.  Jour  Pharm. 
July,  1889. 
being  rejected),  found  in  the  stalks  and  nerves  only  0*2  per  cent,  of 
that  constituent.  Moreover,  he  observed*  that  the  presence  of  these 
latter  is  liable  to  render  the  infusion  gelatinous. 
Although  digital  in  is  insoluble  in  water,  and  hence  the  results  of 
Mr.  Broeker  cannot  be  used  to  prove  that  the  stalks  are  largely  desti- 
tute of  the  water-soluble  active  principles  of  digitalis,  they  would  in- 
dicate that  if  there  was  such  a  radical  diminution  in  the  percentage  of 
one  active  principle,  there  was  in  all. 
In  the  officinal  infusion  of  digitalis,  it  will  be  remembered  that 
powdered  cinnamon  (JNo.  20)  is  directed  to  be  infused  in  connection 
with  powdered  digitalis  (No.  20).  Cinnamon  is  here  employed,  not 
for  any  medicinal  action  it  may  possess,  but  solely  for  the  purpose  of 
flavoring ;  a  purpose  which  it  but  imperfectly  fulfills,  through  the  solu- 
tion of  a  small  quantity  of  volatile  oil  of  cinnamon. 
It  is  of  interest  to  know  whether  the  presence  of  this  volatile  oil 
exerts  any  retarding  influence  upon  the  solution  of  the  water-soluble 
principles  of  digitalis.  To  determine  this  point,  infusions  were  made 
of  digitalis  leaves,  which  had  shown  1*4  grains  of  soluble  solids  in 
each  fluiclounce  of  infusion,  and  cinnamon  water,  the  specific  gravity 
of  which  was  first  taken.  The  result  in  all  cases  indicated  but  0*98 
grains  of  solids  to  the  fluiclounce,  a  decrease  of  0*42  grains,  or  30  per 
cent.  It  may  be  claimed  that  the  officinal  infusion  of  digitalis  is  by 
no  means  analogous  to  cinnamon  water  in  the  amount  of  volatile  oil 
which  it  contains.  But  it  seems  evident  that  the  presence  of  that 
volatile  oil,  however  small  it  may  be  in  amount,  must  exert  a  retard- 
ing influence  upon  the  solution  of  the  digitalis  principles,  and  hence 
powdered  cinnamon  should  be  dropped  from  the  officinal  formula. 
In  reducing  the  strength  of  infusion  of  digitalis  to  7  grains  to  each 
fluidounce,  the  Revision  Committee,  in  the  opinion  of  many,  altered 
the  quantity  in  the  wrong  direction.  It  should  have  been  increased, 
if  anything.  But  as  the  limit  of  regular  saturation  appears  to  be 
about  200  grains  to  the  pint,  it  would  be  better  to  return  to  the  phar- 
macopoeial  strength  of  1870,  i.  e.,  about  7*5  grains  to  the  fluid- 
ounce,  or  120  grains  to  the  pint. 
The  following  is  the  formula  in  use  by  the  writer : 
Take  of  digitalis  leaves,  bruised....;   120  grains, 
water   14J  fhiidounces, 
alcohol..,   "  " 
Macerate  the  digitalis  leaves,  previously  bruised  in  a  wedgwood 
