232 LETTERS TO THE EDITOR. [Jan. 



Betters to the Editor. 



ABOUT LIGHTNINa ON TBEES. 



SIE, — The violent thunderstorms of last summer appear to have 

 brought the above topic to the front on the Continent, as well 

 as amongst your readers. From a paper running through two con- 

 secutive numbers of Le Bois, by M. De La Pinardiere, we learn that 

 the Belgian Administration of Forests and tliat of Telegraph 

 Erection have both given instructions to their officers to collect 

 careful statistics of the effects of future storms. The danger to 

 human life, especially the deaths of two young forest officers while 

 seeking refuge under a tree during one of the violent lightning-dis- 

 charges of last summer, appears mainly to have incited this inquiry. 

 The example might be followed in this country through the agency 

 of one of our societies, or by short notes to your letter columns. 

 Meanwhile we may dismiss this somewhat hot subject, till the 

 proper season, by citing some already-ascertained facts given by your 

 Belgian contemporary. 



First, then, there is a list of trees popularly held to have an 

 immunity from lightning — viz. the beech, birch, maple, and bay 

 tree ; while on the dangerous side have been placed the elm, chest- 

 nut, oak, and pine. Now there are no facts for such a classification. 

 All trees, being without exception conductors of electricity, are 

 liable to be struck. In observations made in England of twenty- 

 eight cases of trees struck by lightning, the following numerical 

 statistics of specific trees were obtained : — 9 oaks, 7 jDoplars, 4 

 maples, 3 willows, 1 horse chestnut, 1 chestnut, 1 walnut, 1 haw- 

 thorn, and 1 elm. The beech, popularly believed to be a safe 

 shelter in a thunderstorm, does not figure in the list; but the haw- 

 thorn does, M'ith a similar supposed immunity from danger. Such 

 details therefore only show that tliese trees are seldom struck. 



Dry sandy soils are bad conductors of electricity. But the crests 

 of mountain ridges lying between deep valleys, sucli as are found 

 in the Central Alps, are particularly dangerous. Should the forester 

 on such a ridge hear the mutterings of a coming thunderstorm, he 

 should descend immediately at least say three hundred yards into the 

 valley. In a quarter of an hour after such a descent by the author, 

 three Scotch firs on the top were struck by lightning. In such 

 mountain regions animals are oftener struck than men ; the shep- 

 herd has been spared amidst his destroyed flock, and a horseman 

 has had to leave his lightning-destroyed steed. 



In certain species of trees, as the poplars, the stroke is seen on 



