of  the  Ashes  of  Plants. 
507 
For  this  purpose  all  the  specimens,  including  four  reported  in 
our  first  paper,  will  be  grouped  together  without  regard  to  soil  or 
variety. 
Average  composition  in  100  parts  of  the  ash  of  Grain  and  Straw  (with  the 
chaff)  of  Barley  : — 
Bariev, 
mean  of  13 
specimens. 
Barley  Straw 
and  Chaff, 
mean  of  5 
specimens. 
Per  centage  of  Ash  . 
2-13 
4-76 
Silica 
25-27 
59-25 
Phosphoric  Acid 
32-05 
4 04 
Sulphuric  Acid 
•95 
2-45 
Carbonic  Acid  . 
•37 
1-76 
Lime 
2-41 
8-84 
Magnesia  .... 
8-39 
2-59 
Peroxide  of  Iron 
•76 
•78 
Potash 
20*30 
14  99 
Soda 
1-22 
1-20 
Chloride  of  Potassium  . 
•68 
• 18 
Chloride  of  Sodium  . 
1-60 
3-92 
100*00 
100-00 
The  foregoing  numbers  may  be  safely  taken  as  an  average  of 
the  mineral  composition  of  the  bailey  crop.  It  only  now  remains 
to  calculate  from  these  data  the  effect  of  a crop  of  barley  upon  the 
mineral  stores  of  the  soil.  48  bushels  of  barley,  at  55  lbs. 
to  the  bushel,  will  weigh  2640  lbs. ; and  allowing  the  straw  and 
chaff  to  be  1£  times  the  weight  of  the  grain  (or  3300  lbs  ),  which 
perhaps  is  a full  proportion,  the  result  will  be  as  follows : — 
Mineral  matter  removed  from  an  acre  of  land,  by  a crop  of  barley,  in  lbs. 
and  tenths : — 
In  the 
In  the  Straw 
In  the 
Grain. 
and  Chaff. 
whole  Crop. 
Silica 
14-2 
93  0 
107-2 
Phosphoric  Acid  . . 
ISO 
6-3 
24-3 
Sulphuric  Acid  . 
•5 
3-8 
4 3 
Carbonic  Acid  . . . 
•2 
2-8 
3-0 
Lime 
1-6 
14-0 
15-6 
Magnesia  .... 
4*7 
4-1 
8-8 
Peroxide  of  Iron  . 
•4 
1-2 
1-6 
Potash 
14-8 
23-5 
38-3 
Soda 
•7 
1-9 
2-6 
Chloride  of  Potassium  . 
•3 
•3 
•6 
Chloride  of  Sodium  . 
•9 
6-1 
7-0 
56-3 
157-0 
213-3 
A glance  at  this  table  and  that  which  was  given  for  oats  will  at 
