193 
table life. Among its separate particles the tiny rootlets can, with ease* 
wind and twist, thereby forming a secure support to the stalk. Vast ex¬ 
tents of country are composed entirely of sand: such as the almost bound¬ 
less deserts of Africa and Asia, the universal sterility of which prove that 
sand alone is not capable of sustaining vegetable existence; but a due 
proportion renders the soil easy to cultivate, warm and productive. Sand 
enters into the composition of plants; in fact it is a part of their food 
“It is not only, as it were, a plate to hold the food upon which the 
living vegetable subsists, as most people suppose, but it is itself one 
of the things that plants absorb into their substance—on which they 
daily feed.” You may easily prove this, by burning any plant you 
choose, and analyzing its ashes; in them you will find a very considerable 
proportion of sand. Wheat ashes contain 28 parts of sand in 100 parts. 
The ashes of barley contain nearly 50 parts of this material in 100. 
Oats 65 per cent. In the hard polished straw of which bonnets are 
made, the proportion of sand is much greater. Sand is always the most 
abundant in those parts of the plants, most requiring strength and hard¬ 
ness. The straw of any grain contains more than ten times the amount 
of sand that the grain itself does ; and the joints or knees of the stalk 
contain more than the smooth shaft. Sir Humphrey Davy found sand 
most abundant in the epidermis or outer hark of plants—this part evi¬ 
dently requiring the most protection. Thus has nature provided that a 
coat of mail shall surround the finely polished shafts of plants, formed 
of the hardest of the earth; thus the bark of the bonnet cane, the sugar 
cane, the corn stalk, and the common reed, and all similar plants, are 
panoplied in an armor of flint, smooth and hard—at once forming protec¬ 
tion, strength and beauty. The question hereupon naturally arises, how 
is the unyielding sand taken up by the plant ; or, in other words, how can 
a plant eat sand ?—they cannot absorb those hard, flinty grits. Ho, they 
cannot use the sand in its natural state ; they do not eat it raw; it has* 
so to speak, to be cooked for them. Plants absorb sand in solution. 
Pain water will somewhat dissolve sand, owing to its containing a minute 
quantity of ammonia; but pure distilled water scarcely makes any impres¬ 
sion on it. Sand is soluble in alkalies; in potash, for instance, you can 
melt sand. The ley that runs from wood ashes will dissolve sand in 
process of time. In all fertile soils there is more or less potash. It ex¬ 
ists naturally in granite soils, from the decomposition of the granite rocks* 
13 
