Mr. C. Tomliuson on some Effects of Lightning. 119 



it came to an oak-tree, which it went half round, grazing the 

 bark, and then continuing the same straight line which it had 

 been following, and killing two sheep, one about two yards in 

 front of the other, both in line. Where it had first struck 

 the ground, it sent the earth and grass to a great height, the 

 leaves of the trees being covered with earth to a height of 

 from fifteen to fifty feet. The earth being washed down by 

 the heavy rain so covered the sheep as to prevent any mark 

 being seen. One of the sheep was bleeding at the mouth, 

 and another had a hoof nearly torn off. The six were lying 

 from one to two yards from each other. A girl who saw 

 them first, and immediately after the stroke, says there was 

 another sheep trying to get up ; she assisted it and it ran off. 

 It does not seem to have been injured, but it had the same 

 dark blue mark as the others up each side and across the 

 kidneys. The tree struck does not look any the worse, nor 

 any other tree near it." 



Certainly, some of the effects described in the above 

 interesting case seem to justify Mr Dudgeon's opinion that 

 the electrical discharge proceeded from the ground upwards. 

 There are recorded cases of this sort, and when these are 

 referred to by Arago, in his celebrated essay " Sur le 

 Tonnerre," contained in the Annuaire pour Van, 1838, it is 

 with some hesitation. If lightning moves with the velocity 

 attributed to it by Wheatstone, how can we tell whether it 

 ascends or descends ? The answer must be, by its effects. 

 This subject was much discussed by the electricians of the 

 last century, in connexion with what the Earl of Stanhope 

 termed " the returning stroke." When a mass of electrified 

 cloud induces an opposite state on the earth's surface, and a 

 disruptive discharge takes place, the neutralization is by no 

 means complete ; a portion of the earth's surface returns to 

 its former excited condition together with the dielectric air 

 above it, and another discharge may take place from the 

 ground upwards, and this at a considerable distance from the 

 inducing system of clouds. In a case related by Mr. Brydone 

 (Phil. Trans. 1787) that occurred in Scotland, a cart laden 

 with coals, drawn by two horses, was proceeding along a 

 road, the carter sitting in front of the cart. The lad and the 

 horses were struck dead, although no lightning was observed 

 near the place. There was a storm a long way off', which Mr. 

 Brydone was watching at the time, but within half an hour 

 of the accident he was on the spot. On examining the wheels 

 of the cart, circular holes were found in the ground, im- 

 mediately under them, about twenty inches in diameter, at 

 which points the iron tires exhibited marks of fusion. The 



