304 Ms On the Food of Plants. 
In my _expermenis, No. 10,,,we. see, by, the luxurtairt 
growth of the cabbage and the wheat, what vegetable matter 
can produce : : ra in Shee of these could any kind of nu- 
triment be, derived from the quartz sand) in which , ape 
spread their roots. 
The same kind of sand ‘in, the vicinity of Bareelona. is, by 
the assistance of a bright sun and, copious irrigation, ren- 
dered exceedingly productive; but then they. spread upon 
the land all the ‘dung they can procure, and not only station 
children and old women on the bighways with little baskets 
to collect this manure as it falls from horses or from, mules, 
but, like the farmers in the south.of France, they pick the 
leaves from. the trees in autumn, and this at a considerable 
expense. Of such importance do they consider vegetable’ 
matter as the food of plants. 
It must be confessed that we have frequently occasion to 
observe plants dependant on the nature of the earth in which 
they are found, and affecting, each its peculiar earth, in which 
they grow spontaneously ad thrive. 
Thus on chalky and calcareous soils we find Thesiwm li- 
nophyllum, Anthyllis vulneraria, Asperula cynanchia, Lotus 
corniculatus, Hippocrepis comosa, Poa cristata ; and. three of 
the Sedums, the S. acre, S. allum, and S. reflecum 3 as on 
the Wiltshire downs, and on the hills round Bath. 
On sand we see drenaria, Rumex acetosella, and all the 
sorrels; the Plantago maritima, the Plantago Coronopus, 
the Onopordum Acanthium, the Sedum Anglicum, and most. 
remarkably the Spartium scoparium. 
On clay, if wet, the Carices, the Junci, Scheenus, Aira 
cespitosa, and Aira cewrulea, Orchis latifolia, and Orchis 
conopsea; if dry, the Primula veris, Orchis mas, Orchis 
maculata, and Poa pratensis. . 
-On bogs, the Eguiseta, Vaccinium uliginosum, Anagallis 
tenella, Scirpus palustris, Menyanthes trifoliata, and ‘Dro- 
sera, delight to dwell. 
On he sca shore, “ia wherever the muriatic salt abounds, 
as near Alicant in Spain, we find Salicornia Europea, four 
species of Salsola, Chenopodium maritimum, and two spe-, 
cies of Mesembryanthemum. 
These 
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