1849.] Eighteenth Memoir on the Law of Storms. 915 



the Pilot at the commencement of the Cyclone, or to meet with its 

 onset a few hours after getting to sea, say in 20° North, their rule 

 must also be the same, namely, to bear up so far as to cross in front of 

 it, and not, which has usually been done, to stand close hauled into 

 the very path of the track.* And recollecting that from False Point the 

 coast trends to the Westward of S. W., and that in 20° North on the 

 meridian of the Light Vessel, a ship is still 120 miles from the Black 

 Pagoda, there need be no fear about making a little Westing at first, 

 for allowing the Cyclone the very worst track we can suppose for a ship 

 in this position, namely, one from S. by E. it is clear that a very short 

 run to the S. W. will place the vessel at a distance from the line of the 

 track and bring the wind to N. N. E. and gradually to North, so as 

 to place her abreast of the centre ; and if the track is from any point 

 more Easterly, as it probably will be, say from S. E. or E. S. E., then 

 the distance to be made will be but short to a Northerly wind. The 

 intelligent mariner may easily by means of a storm card see the truth 

 of these propositions. 



For the set over the Sandheads it may be safe to allow three and a 

 half miles an hour at the onset of a Cyclone, at the Light Vessel, de- 

 creasing to two and even one knot by the time the vessel has passed 

 the parallel of 20°; but also increasing both in breadth and velocity 

 if the Cyclone has lasted any time, and the careful mariner will duly 

 take this into his account, whether standing out or hove too. 



We may further illustrate this by a reference to our Diagram, No. I., 

 upon which we will suppose, to put things almost at the worst, a 

 Cyclone like this of October, with its centre on the position marked 

 for that of the 12th in Lat. 17' 48' North, Long. 89' 18' East, com- 

 ing up on the same track towards False Point, but at the rate of ten 

 miles an hour. This will place it in twelve hours about 20 miles 

 ahead of the spot at which the centre of the 13th is marked, or say in 

 Lat. 19* 17' North, Long. 88* 18' East, and leaves still a distance 

 of something more than 80 miles between its centre at midnight and 

 False Point. Now, though ships would probably be ordered to sea, 

 say by the station vessel (lying outside of the Light Vessel) on the 1 1th, 

 and certainly at daylight on the 12th, we will suppose a vessel so be- 

 lated, or to have mistakenly run in so far, that she can only start from 

 * No doubt to make Southing and to get an offing from Point Palmiras. 



