of  the  Ashes  of  Plants. 
539 
On  the  26th  of  June  the  second  crop  from  the  plot  of  two 
square  yards  was  cut;  it  weighed  84  lbs.  The  grasses  com- 
posing the  meadow  were  principally  Poa  trivialis,  TIolcus  la- 
natus,  Hordeum  pratense,  Avena  pratensis,  and  Lolium  per- 
enne. 
Per  centage  of  Water,  Ash,  and  Sulphur  in  Meadow  Grass  from  Stratton. 
1st  Crop, 
April  30. 
2nd  Crop, 
June  26. 
Water 
87-58 
74-53 
Ash  ou  the  undried  grass  . 
1-2S 
2-24 
Ditto  on  the  dry  grass  . 
10-37 
8-62 
Sulphur  on  the  dry  grass  . 
•197 
•302 
Composition  in  100  parts  of  the  Ash  of  Water-Meadow  Grass.  * 
1st  Crop, 
April  30. 
2nd  Crop, 
June  26. 
Silica  ..... 
9-24 
34-11 
Phosphoric  Acid 
9-31 
5-56 
Sulphuric  Acid 
3-55 
4-23 
Carbonic  Acid  . . . 
11-62 
1-15 
Lime 
9-50 
9-13 
Magnesia  .... 
2-47 
2-49 
Peroxide  of  Iron 
1*31 
•62 
Potash 
50-00 
22-13 
Soda 
•09 
none 
Chloride  of  Potassium  . 
none 
17-40 
Chloride  of  Sodium 
2-91 
3-14 
100-00 
99-96 
In  the  first  crop  of  grass  the  quantity  of  silica  is  small,  that  of 
potash  large,  when  compared  with  the  natural  grasses  before 
analysed.  The  second  crop  has  ■ a mineral  composition  by  no 
means  unlike  the  average  of  these  grasses. 
From  the  data  now  given  we  may  form  a calculation  of  the 
quantity  of  mineral  matter  removed  from  the  soil  in  two  succes- 
sive crops  of  meadow  grass,  where  the  produce  is  unusually  large, 
as  in  the  present  instance. 
The  English  acre  contains  4840  square  yards — it  was  seen 
above  that  the  first  crop  from  2 square  yards  weighed  in  the 
green  state  114  lbs. ; the  second  crop  from  the  same  space  84  lbs. 
Had  the  crop  from  an  acre  been  weighed,  the  produce  would, 
according  to  this  estimate,  in  the  fisrt  case  have  been  27,225  lbs., 
or  about  12  tons  3 cwt. ; in  the  second  19,965  lbs.,  or  8 tons 
184  cwt. 
The  first  crop  of  grass  gave,  in  the  green  state,  1 ’28  per  cent. 
