856 



BULLETIN OF THE BUEEAU OF FISHERIES 



the north (Mitchell, 1881; Harris, 1907, pi. 7). This is also the case along the west 

 coast of Nova Scotia on the one side of the gulf and along Cape Cod on the other; 

 but the flood runs westward into Massachusetts Bay, as might be expected from the 

 trend of the coast line, drawing southward around the tip of Cape Cod into Cape 

 Cod Bay. There is also a flood current from the westward into the latter, resulting 

 from a division of the tidal wave as it strikes the shore line at Manomet Head just 

 east of Plymouth. 



The promontory of Cape Ann also marks a division in the tidal streams; for to 

 the northward of it the flood, setting westward in toward the land, veers to the north, 

 paralleling the coast as far as Cape Elizabeth; to the eastward of Casco Bay the 

 general direction of the flood at its strength is NNE. toward and through the Grand 

 Manan Channel, complicated, however, by the flood currents setting into the bays 

 and rivers. At the mouth of Casco Bay, for example, the tides flood to the north. 

 In the Bay of Fundy the flood sets generally toward the northeast (i.e., inward). 



In a general way the ebb, at its strength, is the reverse of the flood, setting out 

 of the Bay of Fundy in a generally SW. to SSW. direction and around the coast of 

 Nova Scotia to the south and southeast. Along the coast of Maine, from the 

 Grand Manan Channel to Penobscot Bay, the tide ebbs southwesterly; southerly 

 off Casco Bay. In Massachusetts Bay the ebb is generally eastward; southerly 

 along Cape Cod. 



Generally speaking, the velocity of the tidal currents is least along the sector 

 of coast bounded by Cape Cod on the south and Casco Bay on the north, where 

 velocities lower than 1 knot have been recorded at most of the observing stations 

 for the flood at its strength. But the tide flows much more strongly (up to 1.8 

 knot) around the tip of Cape Cod and at the entrance to Boston Harbor. The 

 Bay of Fundy stands at the other extreme, with velocities rising to 2.5 to 3 knots 

 in the Grand Manan Channel; considerably higher even than this near the head of 

 Minas Basm and elsewhere near the head of the bay. The velocity of the tides 

 at strength is about 1 to 1.6 knots along the southern rim of the gulf; 1.5 to 2 knots 

 along the west coast of Nova Scotia and out to the neighboring side of the basin. 



The rise and fall of the tide is greater in the Bay of Fundy than anywhere else 

 in the world; on the other hand, the tidal amplitude is certainly small over the 

 offshore banks, though the rise and fall has not been measured there as yet. 



The following summary of the rise and fall at representative stations, taken 

 from the tide tables of the Atlantic coast (United States Coast and Geodetic Survey, 

 1926), will illustrate the transition from the mouth of the gulf inward along its two 

 sides for ordinary tides: 



Locality 



WESTERN SIDE 



Outer shores of Cape Cod 



Provinoetown 



Gloucester 



Portland 



Bar Harbor, Mount Desert 



Cutler (at western end of Grand Manan ChannelJ 



Rise and 



fall of tide, 



in feet 



4. 3- 7. 1 

 7. 5-11. 1 

 7. 2-10. 8 

 7.9-11.3 

 9.2-12.6 

 12.9-16.3 



Locality 



EASTERN SIDE 



Shelbume, Nova Scotia 



Yarmouth, Nova Scotia 



BAT OF FUNDY 



St. John 



Digby 



Head of Minas.Basin 



Rise and 



fall of tide, 



in feet 



6. a- 7. 9 

 16. 3-17. T 



23. 7-25. 1 

 27. 2-28. 6 

 48. 7-60. 1 



