EFFECT OF FORESTS UPON HAIL-STORMS. 299 



naturalist of bis day, in a note to an address before the New York Horti- 

 cultural Society, August 29, 1826, published some interesting statements 

 upon this point, among which it was said, that the Indians of the west- 

 ern country were accustomed to seek the nearest beech tree for protec- 

 tion during a thunder shower. After some allusion to classical litera- 

 ture to prove a somewhat similar belief among the ancients, with regard 

 to the laurel, he suggests as a practical application that beech groves 

 should be planted near and around dwelling-houses and barns for the 

 immunity of cattle, as well as human beings, from the violence of atmo- 

 spheric electricity, and that solitary beech trees should be planted here 

 and there over every farm and plantation. 



But this is a rule with exceptions,^ and it is well known that fatal 

 injuries from lightning happen to those that seek the shelter of trees in 

 storm. While there must be a silent discharge of electricity from the 

 points and serratures of leaves, which lessens the probabilities of striking 

 in a forest, it will in some soils and situations be unusually liable,^ 

 and for this reason, to some extent a protection to lower objects near 

 them. A house surrounded by high trees at no great distance is seldom 

 struck by lightning. 



INJURIES FROM HAIL-STORMS. 



It is asserted by M. Becquerel, from numerous observations made in 

 France, that hail-storms become more frequent as woodlands are cleared 

 away, and that although such storms may occasionally pass through a 

 forest of small extent, they will sometimes change to rain over a wood- 

 land, and again to hail beyond ; but oftener they will turn aside, or 

 divide as they come to a large wooded area. This may be accounted 

 for from the fact that the moist air that hangs over a woodland from 

 the evaporation of the leaves becomes a conductor of electricity, and 

 thus lessens the effect of storms.^ 



M. Bailie has remarked* that zones of hail-storms in France are pro- 

 foundly modified by local causes, appearing with severity in some dis- 

 tricts, and leaving others intact. They have a preference, so to speak, 

 for certain parts of a country, visiting it often, and producing similar 

 effects, observing therein a singular periodicity, returning at intervals 

 of a certain number of days and hours and then disappearing for a series 

 of years, so that periods of two bad years are separated by periods of 

 good years. When they come, they seldom come singly. He cites from 

 a memoir of M. Becquerel, who shows that forests protect the country 

 to a certain extent beyond them, and that belts of hailstorms are 



1 The Netv York Tribune of September 26, 1873, mentions five instances of the beech 

 beinjT struck, giving date, place, and authorities. 



-Trees in moderately moist ground are but feebly affected, because the electricity of 

 the same name cannot be repelled to a distance in such earth, which is a very bad con- 

 ductor for large charges of electricity. If the tree, on the contrary, is in ground 

 which is very wet and of great extent, it will be strongly influenced, because the elec- 

 tricity of the same name can pass off to a distance in this good conductor. In fact it 

 will be affected in the greatest possible degree if this good conductor is itself in com- 

 munication with other sheets of water of indednite extent. (Lightning Conductor 8 : 

 Etiport of the Commission of the French Academy of Sciences on Lightning Conductors 

 for Powder Magazines ; translated by Commander R. Aulick, United States Navy, p. 4.) 



Saint Pierre suggested that the planting- of trees around habitations would be a 

 security against lightning. {Botanical Harmonies Delineated, p. 65.) 



= The Hon. C. E. Whiting, of Iowa, at a meeting of the Iowa State Horticultural 

 Society in 1870, stated that he had known a severe bail-storm stopped by a grove of 

 trees. {Iiepoi-l of Iowa Stale Horticultural Society for 1869, p. 68.) 



'^ Zones des Orages a Grele: Discussion des Documents anciens pour dix sept T)4pariement8, 

 Par M. J.- B. BaiUe. Atlas Meteor ologique de V Observatoire Imperial, 1866, B. 3. 



