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The Mtiseum Gazette 



dead trees. One is a Scotch fir, one a larch, and the third is 

 a Douglas spruce. 



They are all young, not more than twelve years old, all 

 planted at the same time, and all in good health until three or 

 four years ago. They are surrounded on three sides by other 

 trees of the same age, all of which are in vigorous health. 

 One side they are open to the meadow, and from the centre 

 of them in this aspect a tree has been cut down. Unfortu- 

 nately, no record has been kept as to why this tree was 

 removed, but presumably it was dead, and that its death 

 was obvious at a time when the three behind it and its sides 

 were not seen to be damaged. The problem is, what can 

 have killed these three trees ? It could not have been any- 

 thing in the soil or the exposure, for the trees close around 

 them are flourishing; nor could it have been the attacks of 

 any fungus, for they are of three different species, and they 

 are all quite dead, and all died suddenly at the same time. 

 The only plausible hypothesis seems to be that the central 

 tree (which has been removed) was killed by lightning, and 

 that the globe of sudden and momentary heat which sur- 

 rounded it so injured its three neighbours that they subse- 

 quently died. $ # # The relative position of the four 

 is indicated by these dots, the smaller one representing the 

 position of the one supposed to have been struck. 



MEMORANDA RESPECTING LIGHTNING. 



Wheatstone, by careful experiment, proved that some 

 lightning does not last the thousandth part of a second. In 

 most instances it is probably somewhat longer than this. 



Lightning flashes in most instances pass from one cloud to 

 another, but sometimes from a cloud to the earth. 



The heat attending lightning is intense, but it lasts for an 

 inconceivably short space of time : thus, it may melt metal in 

 contact with gunpowder, and fail to ignite the powder. 



