XX ROYAL SOCIETY OF CANADA 
The central position of Sand Heads, in the Strait of Georgia, makes 
it eminently suitable as a port of reference for other harbours 
throughout that strait. The only data previously available were 
those given in the tide tables issued by the United States Coast 
Survey, which are based upon comparison with Puget Sound, where 
the type of the tide is different in character from the Strait of 
Georgia. These data were far from satisfactory; and the only means 
of securing an improvement, was to obtain observations in the region 
itself. This has now been done; and the result will be further 
improved and extended as time goes on. These new tide tables and 
the accompanying information are much appreciated on the Pacific 
coast. 
At all the stations where observations are taken, the levels are 
recorded permanently by reference to bench-marks. These will be 
invaluable when they come to be connected by some general system 
of levelling. In the meantime, they are of immediate use locally, 
in enabling the true level of high and low water to be known, for 
the purposes of construction in harbours, and for city works, such 
as drainage. At the head of the Bay of Fundy,a good datum level 
is afforded by the Chignecto Marine Railway. Last season, extended 
levels were run around Cumberland Basin, to connect with this datum 
a number of important observations of exceptional high waters. The 
resulting range of the tide was also correlated with observations taken 
by the Admiralty in 1859 in the other arm of the Bay of Fundy, 
namely, at Noel Bay, in Minas Basin. In this way the extreme 
height of the tide is definitely known, which is valuable in preventing 
the flooding of the extensive dyked marshes in these regions. The 
main object of the work was to determine the astronomical conditions 
under which exceptional high water occurs; and to bring this within 
the scope of prediction. 
On the Lower St. Lawrence, the turn of the current in relation 
to the time of high and low water had been determined at several 
points, while the latest Admiralty surveys of the St. Lawrence were 
made from 1885 to 1889; but, unfortunately, the time of the tide itself 
was not known, as there were then no tide tables for the St. Lawrence 
to refer to, or any data by which it could be ascertained. By the 
tidal observations of 1900, the requisite data for the tide itself have 
been secured, and this enables the turn of the current also to be 
known. The information formerly obtained by the Admiralty is thus 
made practically available to mariners for the first time. The local- 
ities for the tidal observations were carefully chosen with this object 
in view. 
