386 EE MARKS ON THE TIDE TABLE. 



Westward ; and when the new Channel Streams make, as the water rises 

 on the shore, this intermediate portion is found to unite with, or to oppose, 

 one or the other of these streams, according as it was before the reverse ; 

 so that, as before mentioned, the line of meeting at low water appears oflf 

 Beachy Head to recommence its Easterly course. This intermediate stream 

 forms a remarkable feature in the tidal system of the Channel ; it is well 

 established, as the line of meeting and of separation occupies a very limited 

 space, and it seems to be entirely due to the contracted form of the Channel 

 in this immediate locality preventing the free escape of the water. 



Admiral W. Bullock, in order to test the point of separation, anchored 

 two vessels a mile apart, between Beachy Head and Dungeness, and found 

 both vessels at the same time to ride with their heads in opposite directions 

 in obedience to the streams, which were then running opposite ways. 



The Channel Stream, which I have described as running between the 

 intermediate stream and the rotatory or mixed streams at the outer ex- 

 tremities of the Channel, pursues a steady course along the main trunk of 

 the strait, slacking only towards high and low water at Dover, when it is pre- 

 paring to invert its course; and, contrary to the generally received opinion 

 of a progressive slack water in a strait having a progressive establishment, 

 this stream has the peculiarity of slacking throughout its whole extent at 

 nearly the same time; and this time, as was anticipated in my former 

 paper ("Phil. Trans.," 1848), corresponds nearly with the time of high 

 and low water on the shore at Dover, the site of the combined wave, and 

 the virtual head of the tide. 



A simple rule thus suffices to guide the sailor up the main Channel 

 Stream. It is, that the stream rzcns toward Dover ivhile the ivater is rising 

 there, and away from it while falling. The tidal hours for Dover, there- 

 fore, answer for the whole of the Channel. 



The meeting of the stream off the Casquets and the Start in the English 

 Channel, and the direction there given to the water at a particular time 

 of the tide, will fully answer for the numerous wrecks about the Channel 

 Islands ; whilst near the Strait of Dover, an unexpected set of the stream 

 directly down upon the Somme, and in a part of the Channel where, from 

 its narrowness, a true stream might be expected, is evidence of the danger 

 of approaching this part of the Channel, if ignorant of the set of the stream. 

 And, most singularly, this occurs exactly in the spot where those disastrous 

 wrecks of the Conqueror and Beliance took place, and where the Ciiraqoa, 

 one of H.M. frigates, so narrowly escaped a similar fate. 



Further particulars on the Tides of the English Channel will be found in 

 the Sailing Directions accompanying the Chart. 



(3.) Southampton, &c. — This port has the singular advantage of having 

 two high waters, which adds not a little to its dock facilities. The same 

 phenomenon is also found in other places within the Isle of Wight, and is 

 owing to the Channel Tide passing round either end of the Isle of Wight, 

 and arriving at the port at different times. 



It will be observed that at Poole the rise and fall is insignificant, while 

 on the opposite side of the Channel we have the gigantic tides of the Bay 

 of St. Malo, a similar feature to that which is found in the Bristol 

 Channel. 



