204 POPULAR LECTURES AND ADDRESSES. 



of Wight, seems to have a continuity of cause with 

 the double low-water at Portland, which is certainly 

 allied to the protracted high-water of Havre a 

 phenomenon quite beyond reach of the Solent's 

 influence. It is probable, therefore, that the 

 double high-water in the Solent and at Christ- 

 church and Poole is influenced sensibly by the 

 current through the Straits of Dover, even though 

 the common explanation attributing them to the 

 Isle of Wight may be in the main correct. 



APPENDIX C. 



ON THE TIDES OF THE SOUTHERN HEMISPHERE 

 AND OF THE MEDITERRANEAN. 



[Abstract of paper by Captain Evans, R.N., F.R.S., and Sir 

 William Thomson, LL.D., F.R.S., read in Section E of 

 the Dubli?i (1878) meeting of t]ie British Association^ 



ON the coasts of the British Islands and 

 generally on the European coasts of the North 

 Atlantic and throughout the North Sea, the tides 

 present in their main features an exceptional 

 simplicity, two almost equally high high- waters and 

 two almost equally low low-waters in the twenty- 

 four hours, with the regular fortnightly inequality of 



