and on the Effects of Lightning on certain Ships. 407 



fell on the truck it shivered the top-gallant mast in pieces so 

 far as the commencement of the chain at h ; here being as- 

 sisted by the chain, it passed on 'without any damage to the 

 topmast, which is extremely worthy of remark, because in the 

 former case, where there was no chain, the top-mast was de- 

 stroyed. 



Having reached the point c, where the chain terminated, 

 it passed with damage over the head of the mast, until again 

 being assisted by the lower chain d. e, it passed "mtliout da- 

 mage to the deck ; on reaching the deck at ^, it passed by 

 means of a bolt through a beam in the forecastle upon the 

 chain cable, and thence into the sea *. 



29. These effects are similar to the former, and show the 

 protection afforded by the chains, and their power of con- 

 ducting heavy discharges of lightning without any of the ill 

 consequences insisted on by Mr. Sturgeon ; since in both 

 cases the chains were in the vicinity of large metallic masses, 

 viz. the iron hoops, iron-bound blocks, &c. about the masts, 

 and in both cases the lightning passed through the hull. 

 Now as all the laws of nature are general, not partial, it is 

 reasonable to infer, that if Mr. Sturgeon's view of a lateral 

 explosion wei'e true, it ought to apply in such palpable cases 

 as these, more especially when he says he can produce a la- 

 teral explosion at 50 feet distance with a jar of only " a quart 

 capacity." 



30. No. 3. The effects of lightning on H.M.S. Snake, is 

 another striking; instance of the general laws we have been 

 contending for. The phsenomena are detailed with peculiar 

 clearness by Capt. Milne in the March number of the Nautical 

 Magazine. The electric fluid entered main truck, shivered 

 royal mast, splintered top-gallant mast; then over chain main 

 topsail tye "without damage to within 8 feet of the deck so far 

 as the topsail halliards. 



Finding, as observed by Captain Milne, an obstruction 

 here in the ropes, it again seized on the mast, and be- 

 came divided at the saddle of main boom ; one portion 

 passed out of quarter-deck port to the sea, the other to lower 

 deck and down the mast, and distributed itself over the hull, 

 affecting persons below. The mast, on being examined at 

 Halifax, was sprung about the partners two inches deep and 

 15 inches round, and \\2i% perfectly hurst asunder at the step; 

 hence the shock had extended to the heel, the electric matter, 

 consequently, must have passed by the metallic bolts in the 

 keelson to the sea. 



* An interesting and authentic account of this circumstance will be 

 found in the Nautical Magazine, vol. viii., p. 114. 



