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equator; diverging as the degrees of longitude enlarge; strongly visible where 
densest, and becoming less visible as it more diverges; till it finds a passage 
to the earth in more temperate climates, or is mingled with the upper air? 
If such an operation of nature were really performed, would it not give all 
the appearance of an aurora borealu? And would not the auroras become 
more frequent after the approach of winter; not only because more visible in 
longer nights, but also because in summer the long presence of the sun may 
soften the surface of the great ice-cake, and render it a conductor, by which 
the accumulation of electricity in the polar regions will be prevented?” 
Nature has done most, where her efforts seem most wanted. In Sect. XIII. 
we showed the peculiarity of the Lapland year, and we cannot help now 
observing her kindness, when the sun no longer spreads his influence of light, 
by substituting the powers of the electric fluid. 
By dancing meteors then, that ceaseless shake 
A waving blaze refracted o’er the heavens, 
And vivid moons, and stars that keener play 
With double lustre from the glossy waste; 
Ev’n in the depth of polar night they find 
A wondrous day: enough to light the chase. 
Or guide their daring steps to Finland fairs. 
Thomson. 
As soon as the Lapland winter ceases, besides the oxygenation of the 
earth from the melting snows, the accumulated electric fluid penetrates the 
ground, and aids the other powers in accelerating the growth of plants. 
That the electric fluid has some sensible effect upon vegetation, even com¬ 
mon observation has pointed out. 
It has been universally noticed that grass grew stronger in patches where 
the earth had been struck with lightning, and that there mushrooms would 
spring up. 
This increased fertility of soil were denoted fairy rings by vulgar super¬ 
stition, who seeing the effect were wont to attribute it to a supernatural cause. 
I remember, says Dr. Darwin, some circles of many yards diameter of this 
kind near Foremark, in Derbyshire, which annually produce large white fun¬ 
guses, and stronger grass, and have done this, I am credibly informed, more 
than thirty years. 
Experiments have been purposely made with the electric fluid to ascer¬ 
tain its influence on vegetation. 
The famous Abbe Nollet, after having discovered the quicker rise of 
