3io 
Pelargonium-Oil. 
Am.  Jour.  Pharm. 
May,  1921. 
periments  have  been  made  with  a  variety  of  P.  radula  (Perfumery 
and  Essential  Oil  Record,  V,  19 14,  p.  423)  ;  but  they  have  not  been 
continued. 
According  to  a  notice  of  Bertoni  (in  the  Coltivatore  ex.  Bull. 
Off.  Gouv.  gen.  de  VAlgerie;  cf.  Schimmel,  Ber.,  1907,  I,  p.  45),  the 
cultivation  of  pelargonium  in  Italy  is  inconsiderable  in  spite  of  the 
rising  consumption  in  the  tobacco  industry  and  its  importance  for 
the  manufacture  of  perfumes.  I  must  confess  that  nothing  is  known 
to  me  about  the  cultivation  of  pelargonium  in  Italy  or  of  its  use  in 
the  manufacture  of  tobacco. 
CULTIVATION. 
The  plant  may  attain  an  age  of  more  than  twelve  years  (Chara- 
bot  and  Gatin,  p.  290).  In  cultivation,  all  plantations  are  renewed 
after  from  five  to  six  years  (Heuze,  p.  307).  The  plant  is  indiffer- 
ent to  great  heat,  but  suffers  if  the  temperature  sinks  to  2°  or  30  C, 
so  that  a  winter  temperature  of  50  C.  may  be  considered  the  lowest 
limit  of  cultivation.  Reunion  and  Algeria,  whose  average  winter 
temperature  is  from  ii°  to  120  C,  are  therefore  much  more  favor- 
able to  the  cultivation  of  the  plant  than  Southern  France,  where  the 
plants  must  be  renewed  every  year  or  else  be  protected  from  the 
cold.  To  grow  exuberantly,  the  plant  needs  a  quantity  of  rain  of  at 
least  700  mm.,  and  a  locality  well  exposed  to  the  sun.  Good  artificial 
irrigation,  as  it  exists  in  Reunion,  increases  the  weight  of  the  crop, 
but  not  the  quantity  of  oil  in  tons.  In  France  and  Algeria,  there- 
fore, this  method  is  not  used,  especially  because  the  soil  is  soon  ex- 
hausted and  gets  a  firm  crust,  which  at  length  does  harm  to  the  plant. 
QUALITY  AND  CULTIVATION  OF  THE  SOIL. 
The  rose-pelargonium  prefers  a  soil  which  is  well  permeable 
and  of  silicious  or  silicious-clayish  quality.  As  the  plant  is  very  sen- 
sitive to  stagnant  water,  the  soil  must  be  perfectly  level  and  deeply 
plowed,  the  plant  being  in  need  of  good  ventilation  to  grow  well. 
By  this  method  also  the  root-stocks  of  Cynodon  dactylon,  the  most 
disagreeable  weed  of  Northern  Africa,  are  removed.  After  every 
cutting  the  rows  are  hewed  through  or  slightly  plowed.  The  quan- 
tity of  manure  and  the  manner  of  its  application  and  distribution  is 
of  great  importance.    Concerning  this  we  have  some  accounts. 
Boutilly  on  Reunion  (p.  179),  for  the  conditions  prevailing 
there,  recommends  an  annual  manuring  of  a  ton;  of  superphosphate 
