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Most often lightning strikes trees growing upon 

 heights, but never such as are situated on the banks of 

 rivers or lakes or in marshy places. It is certain that 

 half the peasants who have perished from lightning have 

 been struck while seeking refuge under trees in dry and 

 elevated spots. 



Trees with fresh sap are never split up by lightning 

 but it often happens that people seeking shelter under 

 their boughs are killed; dead wood only is subject to- 

 destruction, though living trees on elevated ground do 

 actually attract the electric current, a circumstance which 

 is accounted for by the fact that a desiccation of the 

 soil always precedes the natural formation of a barome- 

 trical minimum. Although the tree in such dry places 

 continues to distil oxygen the ground does not yield 

 enough moisture for the hydrogen element needed to 

 carry this away. Hence the vegetation which produced 

 this oxygen retains it, though as explained to its own 

 detriment. The affinity of this gas with the electric spark 

 draws them together, as you will find two vessels burning 

 in proximity on the water eagerly unite. 



Not knowing these natural laws our country people 

 seek refuge from storms under the trees, while the ravens 

 and the rooks, from their careful avoidance of such risks, 

 appear by comparison winged scientists. These birds 

 specially love to build their nests in poplars and birches, 

 but if necessity compels them to select a tree in a dry 

 soil, before beginning to build they peck off the bark 

 upon the boughs on which the nests will rest and dry 

 the twigs; but they will never undertake this labor when 

 the subsoil is damp. A glance at the physical laws of 

 formation of oxo-hydrogen splendidly justifies and explains 

 this caution of the birds, for a tree growing in damp' 

 ground never dries, i. c. never accumulates an excess of 

 oxygen, whilst the opposite must be predicated of trees 

 growing in arid earth. 



A tangible evidence of its electric quality is shown 

 by the influence of lightning on the magnetic needle. 



