S14 Mr Harris on the Utility of fixing 



tallic fastenings as are near, and by the water which is usually 

 found in the vessel, and which operates as a conductor both in- 

 side and out, to equalize and disperse the action. The follow- 

 ing is an interesting case. 



(m) In August 1790, a schooner, on board which Captain 

 White had taken a passage from Quebec to Halifax, experienced 

 a storm of thunder and lightning, in which the foremast of the 

 vessel was struck, and shivered from the top to bottom. Cap- 

 tain White immediately requested the people to sound the well, 

 in order to ascertain if the vessel leaked, not doubting but that 

 the electric fluid must have escaped through the bottom below 

 the line of flotation ; but it did not appear that any damage had 

 been done below. 



37. That our conductors pass near the magazines is allowed, 

 but such is the case in every magazine in Europe defended by 

 lightning-rods, and can be no objection whatever ; indeed, it 

 renders the protection still more effectual, for we well know that 

 the electric matter will never leave a good conductor in the line 

 of action, to pass out of it upon detached or impetfect conduc- 

 tors out of that line *. We may therefore infer, that when- 

 ever the electric matter is fairly led to the keel, the danger is 

 passed. 



38. The sum of what has been advanced concerning the con- 

 ducting power of bodies, then, amounts to this, — conductors of 

 electricity remove by the aptness of their parts that resistance 

 to the passage of the electric agency which it would otherwise 

 experience ; that, consequently, their action is purely passive ; 

 and that they can no more be said to attract or draw down 

 lightning upon a ship, than a dike can be said to attract the 

 water which of itself finds its way through it ; that such passive 

 attraction as this cannot fairly be urged as an ai'gument against 

 lightning conductors, which operate only in conveying away the 

 electric matter when it falls on them ; that we must, therefore, 



• On this principle, Dr Franklin found that a wet rat could not be killed 

 by a discharge of artificial electricity, but that a drt/ one might ; and, on the 

 same principle, it seems desirable to pass some stout copper round and across 

 barrels of gunpowder, so is to facilitate the passage of the electric matter 

 over the surface, and not give it the chance of finding its way through the 

 barrel. 



