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slackens, vre may see its course changed by the wind, when the latter 
is not dead ahead, for. some seconds before the fish falls back into 
fhe warves. According to MoMas the fish is hardly able to rise or 
descend at will, and when it is seen moving up and down along the waves, 
this is probably nothing more than the effect of the current of air 
that rises from the surface, and is formed in the trough of the waves 
I 
just as a stream eddies when it passes a promontory, or from the same , 
cause as that from which the flame of a candle is attracted towards a 
sxirfaoe, if we blow straight towards that surface through a tube, the 
I 
end of which is beside, but behind the candle. 
