413 
and on the Effects of Lightning on certain Ships. 
thickness placed in the wake of the gaff. This is conclu- 
sive of the fallacy of Mr. Sturgeon’s assertion, that any con- 
ductor applied to the mast, would, under the operation of 
lightning, be “ probably peeled from the wood.” 
In the case of the Kingsbridge spire. No. 6. The lightning 
which shivered the tower, fell on a cylindrical iron rod of an 
inch diameter without producing any effect on it. 
In the case of the Rodney, the flash which set the top on 
fire and splintered the masts, was conducted by a short cop- 
per funnel for top-gallant rigging without fusion. 
In the case of the Beagle, No. 7, a shock of lightning 
passed down the conductors without producing any effect on 
them. 
No. 10. A house was struck at Tenterden ; the lightning 
fell on an iron bar three-quarters of an inch square, but pro- 
duced no effect on it.* 
No. 11. A stroke of lightning fell on Mr. West’s house 
at Philadelphia, having a conductor terminating in a brass rod 
ten inches long and a quarter of an inch in diameter ; only a 
few inches of the point were melted, but no damage occurred 
to the buildingf. 
No. 12. On the 19th of April 1827, one of the large New 
York packets, whilst in the Gulph Stream, was assailed by 
two most awful strokes of lightning twice in the same day. 
The first shock was productive of serious and destructive ef- 
fects. The second shock fell on a pointed conductor subse- 
quently hoisted to the main-mast head. This conductor con- 
sisted of an iron chain having links of a quarter of an inch thick 
and two feet in length and turned into hooks at each end, con- 
nected by rings of the same thickness, and one inch annular 
diameter. This conductor was attached to an iron rod placed 
at the mast head, half an inch thick and four feet long. 
The explosion fell in a concentrated form, and with an awful 
crash upon this rod. Although the small chain below was dis- 
jointed and some of the links fused, yet this pointed iron rod 
was only fused for a few inches. The ship in the second case 
escaped da^iger. 
Now these are authenticated cases, and there are numerous 
others which I might adduce, to show how perfectly capacious 
and continuous conductors transmit shocks of lightning. 
44. No good instance can be adduced in which conductors of 
great capacity have been even moderately heated by lightning, 
I do not admit Mr. Sturgeon’s “ on dit ” respecting the con- 
ductor passing through the Nelson Monument in Edin- 
burgh. It is really no evidence whatever on a scientific ques- 
* Philosophical Transactions. f Ibid. 
