lU M. Oh. Martins on Trees Cleft by the 



which may be combined or regarded singly, and may be 

 briefly expressed in the following terms: — 



1*^, That the heat of the summers is no longer sufficient 

 among the Alps to arrest the progression of the glaciers into 

 the lower valleys. 



2f/, That the winters, witliout exactly being colder, pro- 

 duce in our day a greater quantity of snow than in past 

 asres.* 



On Trees cleft by the direct action of Electrical Stortns. 

 By Ch. Martins. 



The passage of electrical storms over the wooded parts of 

 the country is marked by varied effects on the trees which 

 cover it. A great number of them are merely torn up and 

 thrown on the earth, others are uprooted and transported 

 parallel to themselves to great distances. A great number 

 have the heads broken off, and the country is strewed with 

 branches and twigs broken and scattered to a distance. All 

 these effects are well explained by the action of the violent 

 wind which drives the clouds charged with the electricity 

 constituting the electric storm. It is not the same with 

 the cleft trees of which we are about to speak. The ac- 

 tion of the wind cannot explain the appearances which they 

 present. At leaving the ground, or more frequently from 2 

 to 0™-50 from the ground, and for a lengtli varying from 2 

 to 5 metres, these trees are divided into laths, in shreds or 

 splinters, often as small as matches. The Society may ob- 

 serve this in the numerous trunks which I now exhibit, and 

 which were cut in the neighbourhood of Montville and Ma- 

 launay after the celebrated storm of the 19th August 1845. 

 This cleavage never extends to the whole of the tree, but 

 only the half or three-quarters of its thickness. The cleft part 

 is turned sometimes to the side from which the meteor came, 

 at other times to the opposite side. The tree is broken in 



* Bibloth. Univ. de Geneve, Jan. 1849, p. 30. 



