[aaxoxc] DOCHET (ST. CROIX) ISLAND 137 
ledges around the island were probably formerly covered with soil 
raised above the reach of the tide. Since the subsidence appears to 
be still going on, we can foresee the time when the soil of the island 
will, unless artificially prevented, be entirely washed away, leaving 
behind but a series of bare rocky ledges. This, however, is still far 
in the future, and engineering skill can, by the use of retaining walls 
and other appropriate devices, preserve the island practically unchanged 
for many a century to come. 
T'ides.— The tides at the island, as determined by the United 
States Coast Survey and recorded upon their charts (Chart No. 300), 
have an average vertical range of 19-9 feet. The range of the highest 
spring tides is between 22 and 23 feet. These tides cause currents 
in the river of some two miles an hour at the extreme, a rate some- 
times troublesome but never dangerous to navigation, even by small 
boats. The appearance of the island changes much with the tides, for 
the reefs are so elevated and extensive that when the sea is out the size 
of the island is increased several fold (Fig. 3) by an irregular margin, 
in places of rock clad with brown seaweed, and elsewhere of boulders or 
sand, while at high tide but little is to be seen beyond the margin of 
the soil of the main island and the nubbles, which then seem to float 
lightly upon the waves." 
Climate-— The climate of the island may be described in general 
terms as that characteristic of a place half way between equator and 
pole, on the eastern margin of a continent; but it is modified in the 
present case by the very cold water which occupies the deep arm of 
the sea in which the island hes. Hence it presents a marked alter- 
nation between a cold winter and a warm summer, but without great 
extremes, and in summer it is considerably cooler than normal for its 
latitude. The keeper of the light-house on the island, who has noted 
the temperature daily for over twenty years past, informs me that the 
coldest days of winter are about —10° F., but an extreme of —28° F. 
has been noted, and the hottest days of summer average about 85°, 
with a recorded extreme of 92°. A very satisfactory idea of the 
climate of the island can be gathered from the records kept at St. 
Andrews, N.B., which, only six miles away and seated upon the end of 
a long peninsula projecting into Passamaquoddy Bay, must have a 
climate nearly identical with that of the island. The climate of St. 
Andrews, as shown by the averages for a large series of years, is, 

1 In the map, Fig. 3, the high tide mark is shown by the continuous line, 
and low tide by the marginal dotted lines. The angles indicate rocky ledges, 
the circles boulders, and the dots sand. The broken line shows the outline of 
the grassy or wooded upland. 
