THE MOVING WATERS 



of the North Atlantic, separating New Brunswick from 

 Nova Scotia. Its length up to Chignecto Bay is 140 miles 

 and its extreme breadth forty-five miles. The peculiar 

 formation of the bay gives it the greatest tidal range in 

 the world. Its dimensions and shape are exactly right, as 

 a basin which shelves and narrows gradually for the first 

 100 miles and then divides into two long inlets, to give 

 its waters extreme depth ranges. 



All it needs for these is a series of rhythmic impulses — 

 even as the water in a bath, resting upon a curved and 

 sloping base, can be made to swill in rhythmic waves 

 high up on the shallow end by sweeping it regularly with 

 the hand. The ocean tides of the Atlantic coast give the 

 water in the bay the required rhythmic impulses. Rising 

 and falling at the entrance to the bay in twelve-hour 

 periods, the Atlantic tides keep the waters within the bay 

 swinging up and down, so that it really has its own 

 internal tides, which are kept in motion by the regular 

 pulsations from outside. 



At one time the remarkable tides in this area were 

 attributed solely to the passage of the water into the 

 narrow cul-de-sac, but it is now known that they are due 

 to the Atlantic's rhythmic impulses, and the peculiar 

 situation of the bay upon one of the ocean's cotidal lines, 

 where the tidal periods are practically stationary and 

 periodically regular. It is paradoxical that the Atlantic's 

 regular impulses should create such wide variations in 

 tidal range within the bay. At Passamaquoddy Bay, at 

 the southern end of the Bay of Fundy, the rise and fall is 

 about twenty-five feet. But at the northern end, in the 

 narrow upper reaches, the world's greatest tidal heights 

 are reached, averaging sixty feet and sometimes rising as 

 high as seventy- two feet. Yet just across a narrow isthmus, 

 in the Bay Verte (outside the Bay of Fundy) less than 

 twenty miles from where these world's-highest tides 

 occur, the tide rises only four or five feet. 



The estuaries of some of the rivers in the northern 



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