of  the  Ashes  of  Plants. 
517 
The  ripening  of  the  seed  of  a plant  is  very  generally  believed  to 
cause  a far  greater  exhaustion  of  the  nutritive  matters  of  the  soil 
than  any  previous  stage  of  its  growth.  By  some  this  effect  has 
been  ascribed  to  the  mineral  matters  which  the  seed  requires,  and 
which  are  always  of  a more  valuable  character  than  those  which 
are  found  in  other  parts  of  the  plant.  Without  attempting  to 
offer  any  opinion  on  this  question  at  present,  we  may  point  to 
these  analyses  as  proof  of  the  uniform  existence  of  these  more 
important  substances  in  the  ashes  of  all  seeds.  The  per  centage 
of  ash  in  the  above  instances  is  so  very  variable  as  to  hide  in  a 
great  measure  the  significance  of  its  composition  in  different  seeds. 
For  example,  the  ash  of  carrot- seed  contains  only  13  per  cent, 
of  phosphoric  acid,  whilst  that  of  wheat  gives  45  per  cent,  of  the 
same  ingredient.  On  the  other  hand,  the  per  centage  of  ash  in 
wheat  being  167,  that  of  carrot-seed  is  8 "73,  or  5 times  as 
great ; so  that  in  reality,  in  a given  weight  of  the  two  seeds,  that  of 
the  carrot  contains  by  far  the  most  phosphoric  acid. 
Flax. 
Although  the  cultivation  of  flax  is  by  no  means  extended  in 
this  country,  and  a knowledge  of  its  composition  is  on  this  account 
of  less  immediate  interest  to  the  bulk  of  farmers,  the  peculiarity 
of  the  crop  and  the  great  commercial  importance  which  it  pos- 
sesses in  a manufacturing  country  like  England,  have,  for  the  last 
few  years,  drawn  to  the  principles  of  flax  culture  a considerable 
share  of  attention. 
The  greater  part  of  the  exact  knowledge  which  we  at  present 
possess  of  the  composition  of  the  flax  plant,  is  due  to  the 
admirable  researches  of  Sir  Robert  Kane,  who  first  drew  attention 
to  the  ruinous  and  unnecessary  waste  which  took  place  in  the  then 
practised  methods  of  steeping.  Sir  Robert  Kane’s  conclusions 
have  been  on  more  than  one  occasion  brought  into  question, 
although  the  objections  raised  against  them  cannot  be  said  to 
apply  with  any  degree  of  truth  to  the  spirit- — hardly  indeed  to 
the  letter — of  his  assertions ; but  with  the  exception  of  this  trifling 
opposition,  the  views  which  the  above-named  chemist  first 
advanced  have  been  generally  adopted,  upon  a full  belief  of  the 
correctness  of  the  analyses  upon  which  they  were  founded. 
Some  recent  analyses  of  flax,  by  Messrs.  Mayer  and  Brazier,* 
have  corroborated  Dr.  Kane’s  results,  so  far  as  regards  the  com- 
position of  the  plant  as  it  leaves  the  field,  although  they  do  not 
furnish  any  further  information  on  the  points  which  have  been  in 
dispute. 
It  appeared  to  us  that  by  following  a distinct  method  of  in- 
* ‘ Quarterly  Journal  of  the  Chemical  Society  of  London,’  No.  5. 
