tic ecean. Therefore it must be admitted that, since 

 there is an ebbing and flowing of the Atlantic of several 

 feet at the straits of Gibraltar, there must be an ebbing 

 and flowing of tides in the Mediterranean. Indeed it is, 

 though barely, admitted by Mr. Rennell, who says, 

 u It is a common idea, that there are no tides in the 

 Mediterranean. Nor do they indeed rise, in any part 

 of that sea, in a degree sufficient either to effect the 

 usual purposes of laying ships on shore to careen ; or 

 even in many places, so as to effect the senses of those, 

 who are accustomed to view the ordinary rise and fall 

 of tides, on the coasts of the ocean. But that a tide 

 does exist is certain ; and that it rises five and six feet 

 in particular places. "* 



This difference is owing to the following circum- 

 stance. < The wave of tide," says Mr. Ren n ell, v <is 

 suddenly opposed in front by the eastern coast of Tu- 

 nis; and also compressed laterally by the island of 



Sicily."f 



He further says, that " Modern observations point 

 out a rise of about five feet at Venice," the northern ex- 

 tremity of the Adriatic gulf, " but only twelve or thir- 

 teen inches at Maples, and at Euripus."} 



The Marquis de Chabert, during the time of his re- 

 sidence on the coast of Africa in 17^6, observed that 

 the tides rose three feet ; but the marks on the shore 



* Rennell's Herodotus, page 647. f Do. page 657. 

 | Do, Do. page 659. 



