414' Mr. Snow Harris on the Electrical Discha7'ge 



tion. " It is said (observes Mr. Sturgeon) that the lightning 

 rod passing through the Nelson Monument became so hot 

 by lightning that it could not be touched by the hand by the 

 Jirst person who visited it afterwards. Allowing a few minutes 

 to have elapsed between the flash and the person entering 

 the monument, the probability would be that the conductor 

 had been made red-hot." This is of the same character with 

 all Mr. Sturgeon's data; it is generally surmise, the show 

 without the reality; it just amounts to nothing. 



45. I am aware that it has been also supposed that the great 

 conductors of St. Paul's church were heated by lightning, 

 but it is only a supposition. The conductors were not ex- 

 amined before the lightning, which was said to have fallen on 

 them, occurred, so that we cannot be certain that the observed 

 appearances were not originally present after the forging of 

 them ; it is besides very unlikely, that a stroke of lightning 

 should have fallen on this building, capable of rendering bai's 

 of iron, six inches wide and one inch and a half thick, red- 

 hot, without destroying the thin copper covering the ball and 

 cross on the dome of the building, and without the crash of 

 the thunder having been heard over the whole city, no men- 

 tion of which is made; when St. Bride's steeple was struck, 

 the latter was peculiarly remarkable. 



46. There is another instance on record, of the effects of 

 lightning on an iron rod, in Port Royal, Jamaica, mentioned in 

 the Transactions of the Royal Society, the evidence of which 

 seems very incomplete. Two men are said to have perished 

 by lightning near a church wall : that is not improbable : but, 

 on subsequently looking inside the wall, a bar of iron an inch 

 thick, and a foot in length, was found in many places wasted 

 away to the size of a fine wire. Now it does not appear that 

 this bar was examined previously to the occurrence of the 

 lightning ; hence we cannot infer that the wasting was pro- 

 duced by the electric fluid ; more especially as similar ap- 

 pearances are not uncommon in bars of iron erected in church- 

 yards in this country, and which have evidently resulted from 

 oxidation and time. 



47. Seeing then how much evidence we have from actual 

 experience of the protective effect of regular conductors of the 

 ^i$:)orst kind, and their power of transmitting dense explosions 

 of lightning, we may reasonably infer that a conductor of 

 copper equal to a rod of an inch diameter, and extending the 

 'whole length of the 7nast, would be proof against any discharge 

 of lightning ever experienced, as, I think, is shown by the 

 cases in which ships fitted with my conductors have been 

 struck by shocks of lightning without damage. 



