0.99
Cucumber 0.63
Vegetable Marrow 5.10

On examining this table it may be observed that, notwithstanding the
very great variety in the proportion of ash in different plants, some
general relations may be traced. A certain similarity may be observed
between those belonging to the same natural family, the seeds of all the
cereal grains, for instance, containing in round numbers two per cent of
inorganic matters. Leguminous seeds (peas and beans) contain about three
per cent, while in rape-seed, linseed, and the other oily seeds, it
reaches four per cent. In the stems and straws less uniformity exists,
but with the exception of a few extreme cases, the quantity of ash in
general approaches pretty closely to five per cent. Still more
diversified results are obtained from the entire plants; but this
diversity is probably much more apparent than real, and must be, in part
at least, dependent on the proportion existing between the stem and
leaves, for the leaves are peculiarly rich in ash, and a leafy plant
must necessarily yield a higher total percentage of ash, although, if
stems and leaves were separately examined, they might not show so
conspicuous a difference.

The leaves surpass all other parts of plants, in the proportion of
inorganic constituents they contain, the table showing that in some
instances, as in the maple and Jerusalem artichoke, they exceed
one-fourth of the whole weight of the dry matter. In other leaves, and
more especially in those of the coniferae, the proportion is much
smaller. Taking the average of all the analyses hitherto made, it
appears that leaves contain about thirteen per cent of ash, but the
variations on either side are so large that little value is to be
attached to it except as an indication of the general abundance of
mineral matters.

In roots and tubers the variations are less, and all, except the potato
and the turnip, contain about seven per cent of ash.

The smallest proportion of mineral matter is found in wood. In one case
only does the proportion reach five per cent, while the average scarcely
exceeds one, and in the fir the quantity amounts to no more than one
six-hundredth of the dry matter. In the bark the quantity is much
larger, and may be stated at seven per cent.

The general proportion of ash found in different parts of plants is
given in round nu