Rear- Admiral FitzRoy on the Storms of Oct. and Nov. 1859. 65 



pieces on Anglesea Island, and as abundant information has been 

 obtained from Lighthouses, Observatories, and numerous private 

 observers, I would take this earliest opportunity of stating that the 

 combined results of observations prove the storm of October 25th 

 and 26th to have been a complete horizontal cyclone. 



Travelling bodily northward, the area of its sweep being scarcely 

 300 miles in diameter, its influence affected only the breadth of our 

 own Islands (exclusive of the west of Ireland) and the coast of France. 



While the central portion was advancing northward, not uniformly 

 but at an average rate of about twenty miles an hour, the actual 

 velocity of the wind — circling (as against watch-hands) around a 

 small central " lull " — was from forty to nearly eighty miles an hour. 



At places north-westward of its centre, the wind appeared to 

 "back" or "retrograde," shifting from east through north-east, 

 and north to north-west ; while at places eastward of its central 

 passage, the apparent change, or veering, was from east, through 

 south-east, south, south-west, and west. 



Our Channel squadron, not far from the Eddystone, experienced 

 a rapid, indeed almost a sudden shift of the wind from south-east to 

 north-west, being at the time in, or near, the central lull ; while, so 

 near as at Guernsey, the wind veered round by south, regularly, 

 without any lull. This sudden shift off the Eddystone occurred at 

 about three (or soon after), and at nearly half-past five it took place 

 near Reigate, westward of which the central lull passed. 



From this south-eastern part of England, the central portion of 

 the storm moved northward and eastward. Places on the east and 

 north coasts of Scotland had strong easterly or northerly gales a 

 day nearly later than the middle of England. When the ' Royal 

 Charter ' was wrecked, Aberdeen and Banffshire were not disturbed 

 by wind ; but when it blew hardest, from east to north, on that 

 exposed coast, the storm had abated or almost ceased in the Channel 

 and on the south coast of Ireland. 



Further details would be ill-timed now, but they will be given in 

 a paper to the Royal Society, as soon as additional observations 

 from the Continent, and from ships at sea, have been collected and 

 duly combined with other records. 



The storm of the 31st, and 1st of November, was similar in 

 character ; but its central part passed just to the west of Ireland's 

 south-west coast, and thence north-eastward. 



Of both these gales the barometer and thermometer, besides other 

 things, gave ample warning ; and telegraphic notice might have been 

 given in sufficient time from the southern ports to those of the 

 eastern and northern coasts of our Islands. 



As it is the north-west half of the cyclone (from north-east to 

 south-west, true) which is influenced chiefly by the cold, dry, heavy, 

 and positively electrified polar atmospheric current, and the south- 

 west half that shows effects of equatorial streams of air — warm, 

 moist, light, and negatively electrified ; — places over which one part 

 of a cyclone passes are affected differently from others which are 

 traversed by another part of the very same meteor, or atmospheric 



Phil. Mag. S. 4. Vol. 20. No. 130. July 1860. . F 



