CUSP A TE FORELANDS AT BAY OF QUINTE I I I 



no definite statement, for even during calm weather the momen- 

 tum of wind-generated currents causes them to continue for a 

 considerable period, and it is difficult to distinguish positively 

 between these residual currents and the true seiche current. 



In the absence of accurate observations of the time of oscil- 

 lation of the seiche, we have no means of knowing whether the 

 crest of one wave starts the currents through the canal from one 

 direction at the time when the trough of another is at the 

 opposite end of the canal; in other words, we do not know 

 whether the current periodically reaches its greatest possible 

 maximum value. Assuming a mean depth in Lake Ontario of 

 65 feet, and making some allowance for retardation of the 

 advance of the wave-crest up the narrow bay, a calculation of 

 the time of oscillation of the seiche along the line of direction of 

 the most prevalent storms suggests that the periodicity of 

 coincidence of crest and hollow at opposite ends of the canal 

 will not be the same as the period of the seiche. 



The mean depth of the canal is ii feet; the breadth at the 

 bottom, 80 feet; the breadth of the water surface, 125 feet. It 

 may be inferred from the small volume of water moved through 

 the canal by the seiche current that in the much broader, deeper 

 bay the actual currents generated by the seiche oscillation must 

 be very slight. 



Waves. — The effective agents in the transportation of the 

 shore debris are wind-waves, and the longshore currents which 

 are associated with them. The size of the material transported 

 and the rate at which it travels must necessarily depend upon the 

 strength of the waves; these in turn depend upop wind velocity, 

 and, in the Bay of Ouinte, upon wind direction. Observations 

 which have extended over a considerable period have shown that 

 resultant effective transportation along the shores of the Great 

 Lakes depends in part upon the direction of the most prevalent 

 winds, in part upon the length of the stretch of open water 

 across which the acting wind has come. The larger storms 

 usually determine the resultant direction of transportation. Now, 

 in the case of the Bay of Quinte, the steep sides of the valley in 

 which the waters of the bay lie so guides and controls the winds 



