548 A Twenty-third Memoir of the Law of Storms. [No. 6. 



" strikes" the ship ; then it moderates at 10 p. m. but the Barometer is 

 still depressed, and at midnight a third tornado " strikes" the ship ! 



Now, if these singular (we may almost say wonderful) phenomena 

 occurred all within a brief period, say of an hour or even two, we 

 might account for them by supposing the centre for a time stationary, 

 and that the ship was drifted back into the calm vortex a second 

 time, or carried on into it in some way, or that it had in some way 

 vibrated or revolved, as Mr. Eedfield supposes the centre may do 

 to a certain extent, so as to reach the helpless ship again. But an 

 interval of nine hours, that is, from 3 p. M. to midnight seems to 

 put this out of the question ; for the Cyclone, if single, must have 

 curved forward some distance ; though it may possibly have been 

 carrying the ship with it, as in the case of the Briton and Runni- 

 mede which were whirled round and round and carried forwards for 

 hours before they were thrown on shore (see Journ. "Vol. XIV. p. 357 

 Twelfth Memoir) but then in that case the wind would have 

 veered or shifted somewhat, which it did not do with the Portsmouth, 

 The Briton had, like the Portsmouth, two lulls and three onsets of 

 the hurricane, but then the wind was veering all round the com- 

 pass, and the Bunnimede close to her had but one lull ; and the fact 

 of the Portsmouth's Barometer having remained stationary seems 

 conclusive, not only as to there having been double Cyclones follow- 

 ing each other, but moreover that, as we have nearly demonstrated 

 in the case of the Eliza (9th Memoir as before quoted p. 542) 

 this continued depression of the Barometer is what really occurs in 

 such cases, and on this account alone the record of the fact, when- 

 ever and wheresoever it happened, is most important. 



The "bursting up" of the hatches is so loosely described, that we 

 are at some loss how to consider it. It might be a bursting up of the 

 hatches by the force of the wind getting below, which though difficult 

 to conceive in a ship in such weather, would be analogous to what 

 takes place in the great West India Hurricanes, where, when a door 

 or window is burst open the other windows are blown out, and even the 

 roofs blown off if another window on the opposite side is not opened 

 to allow the exit of the air forced in by the hurricane. Or it might 

 be the hatches getting loose by the working of the deck combing, 

 and so falling in; though this would not be "bursting up" or it 



