THE ASH OF PLANTS. 17 
dental also, or in excess above what is really needed by 
the plant, and leaves us to infer that the quantity of 
these bodies absorbed, depends to some extent on the com- 
position of the soil, and is to the same degree independent 
of the wants of vegetation. 
Alkalies in Strand and Marine Plants.—The above 
conclusions cannot as yet be accepted in case of plants 
which grow only near or in salt water. Asparagus, the 
beet and carrot, though native to saline shores, are easily 
capable of inland cultivation, and indeed grow wild in 
total or comparative absence of soda-compounds.* 
The common saltworts, Salsola, and the samphire, Sali 
cornia, are plants, which, unlike those just mentioned, 
never stray inland. Gdbel, who has analyzed these plants 
as occurring on the Caspian steppes, found in the soluble 
part of the ash of the Salsola brachiata, 4.8 per cent of 
potash, and 30.3 per cent of soda, and in the Salicornia 
herbacea, 2.6 per cent of potash and 36.4 per cent of soda; 
the soda constituting in the first instance no less than ‘| ,, 
and in the latter ’|,, of the entire weight, not of the ash, 
but of the air-dry plant. Potash is never absent in these 
forms of vegetation. (Agricultur-Chemie, 3te Auf., p. 66.) 
According to Cadet, (Liebig’s Erndhrung der Veg., p. 
100,) the seeds of the Salsola kali, sown in common garden 
soil, gave a plant which contained both soda and potash; 
from the seeds of this, sown also in garden soil, grew plants 
in which only potash-salts with traces of soda could be 
found, 
Another class of plants—the sea-weeds, (algae,)—derive 
their nutriment exclusively from the sea-water in which 
they are immersed. Though the quantity of potash in sea- 
water is but *|,, that of the soda, it is yet a fact, as shown 
by the analyses of Forchhammer, (Jour fiir Prakt. Chem., 
* This is net, indeed, proved by analysis, in case of the carrot, but is doubt 
less true. 
’ 8* 
