494  Work  in  an  English  Herb  Garden.     { YoveXr^iT" 
It  will  be  seen  from  a  consideration  of  these  results  that  the 
effect  of  fertilizers  upon  the  percentage  of  alkaloid  is  small,  tending 
to  lower  it.  This  tendency,  which  is  most  marked  in  the  case  of 
nitrogenous  manures,  appears  to  be  due  to  the  larger  growth  which 
results  from  such  manuring — the  larger  growth  producing  more 
weight  of  woody  fibre.  In  every  case  the  percentage  of  alkaloid 
compares  favorably  with  that  contained  in  wild  plants,  showing  that 
cultivation  is  advantageous.  As  regards  the  amount  of  plant  harv- 
ested a  rich  nitrogenous  fertilizer  such  as  farmyard  manure  or  a 
mixture  of  sodium  nitrate,  basic  slag  and  kainite  will  increase  it 
several  fold  if  the  soil  is  not  already  a  rich  one. 
These  results  indicate  that  the  stage  of  growth  at  which  the 
plants  are  harvested  is  not  important  at  least  as  regards  alkaloidal 
content,  provided  that  the  plant  has  not  begun  to  fade  when  there 
is  a  rapid  loss  of  strength,  but  it  appears  as  is  shown  below  that 
adverse  weather  conditions  may  be  the  cause  of  variations. 
In  the  following  table  the  percentages  of  alkaloid  present  in  the 
dry  stem  and  leaf  are  shown  in  parallel  columns  with  the  amount 
of  sunshine  and  rainfall  recorded  in  London,  16  miles  distant  from 
the  farm. 
Year 
Percentage  of 
alkaloid  in  stem 
and  leaf 
Total  hours  sunshine 
May  1st  to  June  30th 
Rainfall 
(Same  period) 
I905 
O.38 
387  hours 
5 .48  inches. 
1906 
0-54 
361  hours 
3 . 86  inches. 
1907 
0-34 
290  hours 
3 . 54  inches. 
1909 
O.48 
387  hours 
5.44  inches. 
1910 
O.61 
360  hours 
4.08  inches. 
I9II 
0-59 
404  hours 
3 . 62  inches. 
1912 
0-59 
360  hours 
4.48  inches. 
I9I3 
O.65 
410  hours 
2 . 20  inches. 
It  will  be  seen  that  the  highest  percentages  of  alkaloid  were  ob- 
served in  the  driest  and  sunniest  seasons  while  the  low  percentages 
found  in  1905  and  1907  are  explained  by  the  heavy  rainfall  in  the 
former  and  the  lack  of  sunshine  in  the  latter  season. 
Belladonna  Roots. 
Belladonna  root  of  commerce  varies  greatly  in  alkaloidal  strength. 
In  a  number  of  analyses  made  of  commercial  roots,  variations  from 
