

Oa. XXL] 



LAKE ERIE— THE MEDITERRANEAN. 



561 



') 



» 



'om 



the other, though, the distance is nearly seventy miles. At 

 Calcutta it sometimes occasions an instantaneous rise of five 

 feet ; and both here, and in every other part of its track, 

 the boats, on its approach, immediately quit the shore, and 

 make for safety to the middle of the river. In the channels, 



between the islands m the mouth of the Megna, the height 

 of the Bore is said to exceed twelve feet ; and is so terrific 

 in its appearance, and dangerous in its consequences, that 

 no boat will venture to pass a spring tide. 5 * These waves 

 may sometimes cause inundations, undermine cliffs, and still 

 more frequently sweep away trees and land animals from low 

 shores, so that they may be carried down, and ultimately 



submar 



Lake Erie. — In 



North 



American lakes, the continuance of a strong wind in one 

 direction often causes the elevation of the water, and its accu- 

 mulation on the leeward side ; and while the equilibrium is 

 restoring itself, powerful currents are occasioned. In Octo- 

 ber 1833, a strong current in Lake Erie, caused partly by 

 the set of the waters towards the outlet of the lake, and 

 partly by the prevailing wind, burst a passage through the 

 extensive peninsula called Long Point, and soon excavated a 

 channel more than nine feet deep and nine hundred feet 

 wide, which was afterwards widened and deepened.f On the 

 opposite, or southern coast of this lake, in front of the town 

 of Cleveland, the degradation of the cliffs had been so rapid 

 for several years preceding a survey 



m 



reaten many towns with demolition. J 



Mediterranean. — It is well known that a powerful current 



m 



the late Admiral Smyth found, during his survey, that the 

 central current ran constantly at the rate of from three to 

 six miles an hour eastward into the inland sea, the body of 



water being three miles and a half wide, 

 two lateral current 



But there are also 



■s 



one on the European, and one on the 



m about two mi 



* Rennell, Phil. Trans. 1781. 

 t MS. of Capt. Bayfield, R N. 



VOL. I. 



t Silliman's Journ. vol. xxxiy. p. 349. 







