EFFECT OF WESTERLY WINDS ON THE CHANNEL. 381 



There is another circumstance to be taken into the ac- 

 count; which is, that the shore of Boulogne, presenting a 

 direct obstacle to the water impelled by the westerly winds, 

 will occsaion a higher level of the sea there than elsewhere ; 

 and of course a stronger^ linej of current towards the 

 Goodwin. 



It must, therefore, be inferred, that a ship, passing the Dangerous con« 

 Strait of Dover, at the back of the Goodwin Sands, during ^ s " enceof 

 the prevalence of strong W. or SW. winds, will be carried 

 many miles to the northward of her reckoning ; and if 

 compelled to depend on it, may be subject to great hazard 

 from the Goodwin. 



It will be understood, of course, that although the The regular 

 stream of current has been considered here (in order to muchtiie same 

 simplify the subject), yet that, in the application of these Iaw s as the cur- 

 remarks, the regular tides must also be taken into the ac- re 

 count. Bnt from my ignorance of their detail, I can say 

 no more than that I conceive, that the great body of the tide 

 from the Channel must be subject to much the same laws, 

 as the current itself. The opposite tide will donbtless 

 occasion various inflexions of the current, as it blends itself 

 with it : or may absolutely snspend it: and the subject can. 

 never be perfectly understood, without a particular atten- 

 tion to the velocity and direction of the tides in moderate 

 weather, to serve as a ground-work*. 

 I am, with great respect, 

 Dear Sir, 

 Your faithful humble Servant, 



J. RENNELL. 



VIII. 



On dead Lime, by Mr. Bucholz +. 



IT has long ago been said, that under certain circumstances 

 which are not yet well ascertained, and particularly after 



* Meffrs. Lawrie and Whittle's publication allows the tides in 

 this quarter a velocity of one mile and a half per hour at the springs ; 

 half a mile at the neaps. The Britannia's accident happened at 

 dead neaps. 



f Journal des Mines, vol. xxii, p. 234. 



a violent 



