Tides in the Mediterranean and Adjacent Seas 



441 



Dawson (see Table 66) Krummel (1911, vol. II, p. 328) has given a new 

 presentation of the co-tidal lines, which are essentially the same as the chart 

 of Harris. Springstubbe (1934) has given a hydrodynamical analysis of the 

 entire tidal phenomena of this adjacent sea based on revised observations. 

 Figure 188 shows the co-tidal lines (referred to 60° W.) and co-range lines 



70°W 



Fig. 



70° W 65° 60° 



188. Co-tidal lines ( referred to 60° W.) and co-range lines for spring tide in m. 



of the spring tide (in m). They are intended to give only an approximate 

 picture of the tidal process in the intern part of the Gulf; especially the 

 distribution of the range remains very hypothetical. The chart shows the centre 

 of the amphidromy near 61°W. and 48i°N., north-west of the Magdalen 

 Islands. The vast areas of the narrow north-east canal have almost syn- 

 chronous tides with establishments between 10 h and 11 h. This entire north- 

 eastern section probably co-oscillates with the tides of the middle of the Gulf. 

 The same is the case for the funnel formed by the river estuary. After the 

 junction with the Saguenay River, the tide wave is changed into a progressive 

 wave moving up the St. Lawrence River. Near Grosse Isle the wave attains 

 its largest amplitude 58 m ( 19 ft) at spring tide; it travels up to 67 nm (135 km) 

 beyond Quebec in 4| h with retarding phase and even farther till Lake 

 St. Peter. In Trois Rivieres, at the lower outlet of the lake, there is still 30 cm 

 spring tide range (according to Krummel). 



In the south-western section of the Gulf, the co-tidal lines are very much 

 crowded and this part of the amphidromy is probably of the character of 

 a standing wave. The Northumberland Strait behaves like a canal open at 

 both ends, whose water-masses can be made to oscillate from both sides. 

 The entire south-eastern section of the Gulf behind the Cabot Strait has 

 an establishment of approximately 8| h. At this point the influence of the 



