SOME MODERN ROCK-BUILDING. 41 



The familiar explanation of the phenomenal tides of the bay 

 being correct, viz., that, during the rise of the tide, as the Nova 

 Scotia and New Brunswick shores approach each other, the wat- 

 ers become crowded and therefore increase in vertical height, the 

 surface of the water at high tide is not a level but a slope from 

 the head to the mouth of the bay; and, as the same conditions 

 apply up the tidal streams, a continuous high water slope then 

 exists from the highest tidal point in the rivers to the mouth of 

 the bay. 



The existence of this high water slope is proved and illus- 

 trated at a point in the Tantramar River known as Rampastme 

 Neck. Here the river makes a beautiful serpentine, doubling 

 back on itself so as to form a peninsula with a narrow isthmus. 

 The isthmus is overflowed at spring tides. When it is being over- 

 flowed by the rising tide the water comes on from the up strean:i 

 side, where it is from one to two feet higher than on the down 

 stream side. The distance around the peninsula being about 

 three miles, the high water surface shows here a slope of about 

 4 inches to the. mile, or 4 feet in 12 miles. Hence it is plain that 

 the higher we ascend the tidal streams the greater is the height 

 of the tid , or, in other words, the further fiom the earth's cen- 

 tre is the high water surface. At the same time, as we leave the 

 bay and ascend the rivers, the less is the difierence between the 

 high and low water surfaces, owing to the upward slope of the 

 bottom ofthe streams being greater than that of the high water 

 slope. 



The tides of the Bay of Fundy are not only pheno'uenal in 

 height but also in the difference of height between spring and 

 neap tides. The s})ring tides occur of course at the };eriods of 

 new and full moon. But new moon tides are not the ?ame in 

 height as those occurring at the previous or next full moon. 

 Whichever of these phases occurs more nearly at the time ofthe 

 moon's perigee brings the highest tides of the month. And the 

 more nearly the phase and perigee approach each other the 

 higher will l:ie that set of tides. It is then that for eeveral suc- 

 cessive tides the water is from one to six feet higher thr.n the 

 mar.:h level, and would overflow them.arsh except for the [ivo- 

 tecting dykes. At the alternate period of spring tides the water 

 barelv rises as high as the marsh level. At :\11 cthe.- tides, the 



