308 Ml- Harris on the Ut'iMy of fixing 



fused by electricity * ; on the contrary, we find that very heavy 

 electrical discharges have been transmitted, without fusion, by 

 small masses of metal. Amongst many instances, may be men- 

 tioned the following : — In the explosion which struck Mr West's 

 house f, the lightning fell upon a spike ten inches long and a 

 quarter of an inch in diameter— only three inches of the fine point 

 were fused. The spike of the conductor on the Packet ship, 

 New York, and on which a tremendous explosion fell, consisted of 

 an iron-rod, four feet long and half an inch in diameter — it was 

 only melted near its extremity for afezo inches ; the chain-con- 

 ductor consisted of iron-wire, of one quarter of an inch in dia- 

 meter, yet only a few of the links were melted. In the case given 

 of the Etna, the whole explosion seems to have been transmitted 



• It has been recorded, that the great conductors of St Paul's Church, 

 in London, had marks of having been made red hot bj lightning ; but it 

 seems, on consideration, that inasmuch as these conductors wei-e not minute- 

 ly examined previously to the lightning which is supposed to have fallen on 

 them, we can never be certain that the marks were not there originally, and 

 resulted from the forging of them : moreover, it is difficult to imagine that 

 a stroke of lightning should have fallen on this building capable of rendering 

 a stout bar of iron, six inches wide, red hot, and yet not have annihilated the 

 thin gilding about the ball and cross, and without the crash of the thunder 

 having been heard over the whole city — no mention of which is made. 

 When St Bride's steeple was struck such was peculiarly remarkable. If, 

 however, we admit the evidence, it is highly conclusive as to the value of 

 lightning-conductors, since the former church of St Paul's, not defended by a 

 lightning-conductor, was twice struck by liglitning, and much damaged ; and 

 it would also tend to shew, that a flash of lightning, capable of rendering bars 

 of iron, six inches wide and one inch and a half thick, red hot, could not fuse 

 the small mass of thin copper covering the ball. The original ball and cross 

 on which this lightning is said to have fallen may be inspected at the Coli- 

 seum, London. 



There is another case of the efFects of lightning on an iron-rod, in Port 

 Royal, Jamaica, mentioned by Captain Dibdin, of a merchant vessel, and 

 given in the Transactions of the lloyal Society, the evidence of which is by 

 no means complete. Two men are said to have been killed by a flash of 

 lio-htning near a church wall : — on looking inside the wall, a bar of iron, of an 

 inch thick and a foot long, was found to have been wasted away in many 

 places, so as to be reduced in size to a fine wire ; but it does not appear that 

 the bar was examined before the lightning happened, so that we cannot infer 

 that the lightning was tho cause ; more especially as the appearance described 

 is very common on bars of iron in church-yards, in this country, which have 

 evidently been the result of oxidation and time. 

 -f- Priestley's History of Electricity. 



