and on the Effects of Lightning on certain Ships. 409 



" At the time alluded to, I was first Lieutenant of the 

 Beagle, and was attending- to the duty on deck. She was at 

 anchor off Monte Video, in the Rio de la Plata, a part of the 

 world very often visited by.severe lightning storms.. Flaving 

 been on board H.M. ship Thetis at Rio Janeiro a few years 

 before, when her foremast was entirely destroyed by lightnings 

 my attention was always particularly divacted to approaching 

 electric storms, and especially on the occasion alluded to, as 

 the storm was unusually severe. The flashes succeeded each 

 other in rapid succession, and were gradually approaching; 

 and I was watching aloft for them when the ship was appa- 

 rently wrapt in a blaze of fire, accompanied by a simidtaneous 

 crash, which was equal if not superior to the shock I felt in 

 the Thetis ; one of the clouds by which we were enveloped 

 had evidently burst upon the vessel, and as the mainmast 

 appeared for the instant to be in a mass of fire, I felt certain 

 'i-hat the lightning had passed down the conductor on that 

 mast ; the vessel was shaken by the shock, and an unusual 

 tremulous motion could be distinctly felt. As soon as I had 

 recovered from the surprise of the moment, I ran down 

 below to state what I saw, and to see if the conductors be- 

 low had been affected; and just as I entered the gun-room, 

 the purser, Mr. Rowlett, ran out of his cabin, (along the 

 beam of which a main branch of the conductor passed) 

 and said that he was sure the lightning had passed down 

 the conductor, for at the moment of the shock he heard 

 a sound like rushing water passing along the beam. Not the 

 slightest ill consequence was experienced ; and I cannot re- 

 frain from expressing my conviction, that had it not been for 

 the conductor the results wouUl have been of very serious 

 moment. 



" This was not the only instance where we consider that the 

 vessel had been saved from being damaged by lightning by 

 Mr. Harris's conductors; and I believe that in saying 1 had 

 the most perfect confidence in the protection which those 

 conductors afforded us, I express the opinion of every officer 

 and man in the ship. 



" Not being sufficiently acquainted with electrical experi- 

 ments, I cannot remark upon those you iiave adduced in sup- 

 port of your opinions detrimental to Mr. Harris's conductors. 



" I can, therefore, only repeat my conviction that the Beagle 

 was struck by lightning in tlie usual way, and certainly with- 

 out any lateral explosion or other ill effects similar to those 

 you insist on in your Annals of Electricity." 



35. Now these facts are totally subversive of all Mr, Stur- 

 geon has advanced concerning his destructive lateral explosion 



Fhil. Mag. S. 3. Vol. 16. No. 104'. May 1840. 2 E 



