708 
CAPTAIN F. W. BEECHEY ON THE TIDAL STREAMS OF 
Comparison 
of time of 
slack water 
in the North 
Sea with the 
time of high 
water at 
Dover. 
Comparison 
of time of 
slack water 
in the En- 
glish Chan- 
nel with high 
water at 
Dover. 
to run to the northward, and on the western side of the Channel has succeeded, the 
North Sea (or outer) stream being in that part favourable to it ; but on the eastern 
side of the Channel, the stream coming round the Texel forces its way up the Channel, 
and creates a temporary disturbance, which is no doubt the cause of the retardation 
of the turn of the stream in this vicinity. 
The two consecutive charts strengthen this supposition, by exhibiting the Texel 
stream receding as the Channel stream gains strength. 
If, then, we except such observations as are shown to be due to the disturbance 
from the Texel tide, we shall find that in the whole extent of channel from Cromer to 
the North Foreland, there is not half an hour of retardation in the time of slack water 
from the time of high water at Dover, while in the establishments there is an increase 
of at least Jive hours. That we may appreciate this very small difference of the time 
of slack water throughout the Channel and the time of high water at Dover, let us 
inquire what takes place in parts of the North Sea, which exhibit the ordinary 
phenomena of tides under the influence of a progressive wave, such for instance, as 
are comprised in the space between Kinnaird’s Head and the estuary of Lynn. There 
is in this space an increase of tidal establishment of five hours, an amount about 
equal to that which exists between Lynn and Dover. By the Admiralty Tide Tables, 
it will be seen that in this space there are nearly five hours’ retardation in the time of 
slack water in the offing, making at least, hour for hour in the change of the stream 
with the change of establishment-, whilst in the North Sea, in the same change 
of establishment, there is scarcely half an hour dijference of time in the change of 
stream. 
If now we take the English Channel, we shall find half-way between the Start and 
Alderney, that the stream turns with the high water at Dover. Off Portland, nine 
minutes before ; off St. Albans, three minutes before ; between the Isle of Wight and 
Cape Barfleur,^^ifeew minutes after-, and so we run on, the differences varying from 
eight minutes one way to an extreme of forty-two minutes the other In the Baie de 
la Seine, the turn of the stream is earlier in the western part than towards its eastern 
extremity, but the formation of the coast about Cape Barfleur will fully account for 
this. 
In the eastern part of the Baie de la Seine a retardation occurs towards the Somme ; 
in that direction the turn of the stream, on the south side of the Channel, is an hour 
later than on the north side opposite; the observations, however, upon that coast are 
not given in a manner sufficiently clear, and they were made many years ago, and 
compared with the establishments of ports, which might not at that time have been 
very accurately determined; therefore I would not dwell much upon them’^. 
Upon the whole, therefore, judging from the observations which have been collected, 
there seems to be sufficient evidence to warrant the conclusion, that, with the excep- 
* The vessel now about to sail to continue this inquiry, will, it is hoped, get some observations in this 
quarter. — November 5. Recent observations have shown these intervals to be in excess. 
