he oat, of which
very complete analyses have been made at different periods of its
growth:--

_Proportion of Ash in different parts of the Oat at different periods of
its growth._

+--------------+---------+---------+--------+------------+
| | | | | Grain |
| Date. | Stalks. | Leaves. | Chaff. | with husk. |
+--------------+---------+---------+--------+------------+
| 2d July | 7.83 | 11.35 | ... | 4.91 |
| 9th July | 7.80 | 12.20 | ... | 4.36 |
| 16th July | 7.94 | 12.61 | 6.00 | 3.38 |
| 23d July | 7.99 | 16.45 | 9.11 | 3.62 |
| 30th July | 7.45 | 16.44 | 12.28 | 4.22 |
| 5th August | 7.63 | 16.05 | 13.75 | 4.31 |
| 13th August | 6.62 | 20.47 | 18.68 | 4.07 |
| 20th August | 6.66 | 21.14 | 21.07 | 3.64 |
| 27th August | 7.71 | 22.13 | 22.46 | 3.51 |
| 3d September | 8.35 | 20.90 | 27.47 | 3.65 |
+--------------+---------+---------+--------+------------+

The increase is here principally confined to the leaves and chaff, while
the stalks, which owe their strength to a considerable extent to the
inorganic matters they contain, are equally supplied at all periods of
their growth. In the grain only is there a diminution, but this is
apparent and not real, and is due to the fact that the determination of
the quantity of ash, as made on the grain with its husk, and the former,
which contains only a small quantity of mineral matters, increases much
more rapidly in weight than the latter, when it approaches the period of
ripening, and it is accordingly during the last three weeks of its
growth that this diminution becomes apparent.

The nature of the soil has also a very important influence on the
proportion of mineral matters, and of this an interesting illustration
is given in the following table, which shows the quantities found in the
grain and straw of the same variety of the pea grown on fourteen
different soils:--

+----+-------+--------+
| | Seed. | Straw. |
+----+-------+--------+
| 1 | 2.30 | |
| 2 | 3.25 | 3.43 |
| 3 | 4.27 | 3.62 |
| 4 | 3.40 | 3.39 |
| 5 | 2.99 | 3.90 |
| 6 | 3.19 | 6.80 |
| 7 | 2.53 | 3.90 |
| 8 | 2.27 | 6.59 |
| 9 | 2.69 | 3.49 |
| 10 | 1.61 | 3.91 |
| 11 | 3.11 | 5.28 |
| 12 | 3.34 | 7.57 |
| 13 | 2.78 | 3.76 |
| 14 | 3.01