240 
Method  of  Cleaning  Digitalis. 
Am.  Jour.  Pharm. 
April,  1918. 
during  dry  spells.  Very  few  plants  died  during  the  season.  The 
harvesting,  which  was  done  the  latter  part  of  September  and  the 
first  of  October,  was  practically  completed  before  freezing  weather 
set  in,  although  there  had  been  some  slight  frost.  The  total  harvest 
represented  approximately  600  Kg.  of  fresh  leaves.  The  collecting 
was  done  largely  by  the  students  of  the  College  of  Pharmacy.  All 
of  the  leaves  were  collected  from  plants  of  the  first  year's  growth. 
The  leaves  were  collected  by  grasping  a  handful  and  cutting  near 
the  ground  with  a  sharp  knife,  the  lower  parts  of  the  petioles  being 
left  with  the  base  of  the  plant.  The  more  heavily  laminated  upper 
portions  of  the  petioles  were  for  the  most  part  included  with  the 
drug  collected.  Only  the  rich  green  fully  matured  leaves  were  se- 
lected. The  average  yield  of  the  green  leaves,  as  determined  by 
weighing  the  product  from  500  plants,  was  240  grammes  per  plant. 
After  collecting  the  leaves  were  taken  into  the  Medicinal  Plant 
Laboratory,  where  as  much  adhering  soil  as  possible  was  removed 
by  brushing.  On  account  of  the  large  quantity  of  drug  collected  it 
was  impractical  to  hand  brush  the  entire  lot. 
The  soil  in  all  of  the  plots  in  which  the  digitalis  was  grown  was 
rather  rich  in  humus  admixed  with  sandy  loam.  The  major  portion 
of  the  ground  was  campus  ground  in  lawn  the  preceding  year  and 
was  plowed  late  in  the  spring.  Attention  should  also  be  called  to 
the  fact  that  the  plantings  were  for  the  most  part  adjoining  a  dusty 
and  much-used  driveway.  During  dry  spells  plants  near  the  road- 
way were  frequently  covered  with  a  grayish- white  dust  from  the 
road.  A  number  of  rains  just  prior  to  collecting  apparently  re- 
moved the  majority  of  the  dust. 
After  brushing,  the  weighed  leaves  were  spread  one  layer  deep 
on  screens  or  tin  trays  and  placed  in  drying  ovens  which  were  heated 
by  gas.  On  account  of  limited  oven  space  the  preliminary  drying 
of  part  of  the  crop  was  carried  out  by  placing  the  leaves  on  window 
screens,  and  these  were  then  placed  in  the  laboratory ;  the  finishing, 
however,  was  done  in  the  ovens.  A  temperature  of  approximately 
80  degrees  Centigrade  was  maintained  until  the  petioles  would  break 
with  a  sharp  fracture.  Previous  determinations  have  shown  from 
two  to  four  per  cent,  of  moisture  remaining  in  the  leaves  at  this 
stage.  The  dried  leaves  were  then  weighed  and  the  percentage  of 
moisture  lost  determined.  The  average  of  numerous  determina- 
tions showed  a  loss  in  weight  on  drying  of  between  80  and  82  per 
cent. 
