160 BLIGHTS. 
sufficiently into account the power of certain winds, 
particularly when conveyed in narrow streams 
along the course of vallies. But, since no wind is 
envariably blighting, there probably exists in some 
cases a peculiar quality conveyed by it, which very 
likely is electricity in some form, knowing as we do, 
how often streams of electric fluid affect vegetation 
destructively for great distances in narrow lines ; 
at other times, the wind itself, void of any peculiar, 
contained quality, appears to act detrimentally on 
trees and herbs by its continued current restraining 
and then staying altogether the circulation of the 
sap and fluid, while again, some winds as accompa- 
nied by some admixture of moisture in certain 
proportions, or by being peculiarly drying, have 
the capability of calling into existence, insects 
which themselves are the efficient agents in the 
blight. Electric matter as a blight certainly exer- 
cises its effects on some trees and plants in prefe- 
rence to others; thus, I have seen sting-nettles and 
the leaves of some particular kinds of trees alone 
affected after the prevalence of lightning, and there 
is reason to suppose it may act in a manner and 
on a scale quite unexpected by us in its latent or 
unseen state when the atmosphere is surcharged 
with it, and conveyed in various directions by cur- 
rents of air setin motion. That narrow currents 
of wind will by continued action on vegetation for 
some time, and even perhaps in some cases for short 
periods, produce blighting effects, is I imagine, 
pretty evident. It will be seen in another place 
how decided is the influence of the south-west wind 
in checking the efforts of growth in trees, and this 
same phenomenon may by reason be classified 
together with the still more evident (because quicker) 
effect exerted by the same wind in its production 
of blight on apple bud and blossom when the 
trees are situated in vallies and low spots towards 
