392 Beck on Salt Storms, &c. 
by the saline quality of the air? The native plants are 
doubtless accustomed to its action, and do not so sensibly feel 
its injurious effects. And if the Egyptian air is so very pene- 
trating from this very cause, as to produce ophthalmia, may 
we not rationally conclude, that its influence must be equally 
injurious to plants not accustomed to it. 
Another illustration of the influence of salt on vegetation is 
to be found in the Dead Sea or Lake Asphaltites. ‘In Lake 
Asphaltites,” says Volney, “there is neither animal nor 
vegetable life. o verdure is to be seen on its banks, nor 
fish. to be found. within its waters: but it is not true, that its 
exhalations are pestiferous, so as to destroy birds flying over 
it. It is not uncommon to see swallows skimming its surface, 
and dipping for the water necessary to build their nests. The 
trwe cause which deprives it of vegetables and animals is the 
extreme saltness of the water, which is vastly stronger than 
that of the sea, The soil around it, equally impregnated with 
this salt, produces no plants, and the air itself, which becomes 
loaded with it from evaporation, and which receives also the 
suiphureous and bituminous vapors, cannot be favorable to 
pgs spoon: hence the ey aspect which reigns around this 
lake. 
3. In what way die the salt operate in producing its 
deleterious effects on the leaves of vegetables? It is by no 
means easy to answer this question. It cannot be by shutting 
up the pores of the leaf, and thus obstructing its perspiration. 
It is well known that when the surfaces of leaves are covered 
with oil, they will soon die.t But salt water is certainly not 
sufficiently viscid to actin a similar w way. 
‘Nor can it be satisfactorily attributed to the difference 
of structure between maritime and land plants. There is 
some difference indeed between many of these, maritime 
plants being generally covered by a pubescence, of which 
most land plants are destitute. It is idle however to suppose 
that the object of this covering is to protect maritime plants 
* Volney’s Travels in Syria and pe Vol. 1, p. 217. 
+ Darwin’s Botanie Garden, p. 256 . 
