10 ROYAL SOCIETY OF CANADA 
own account, may prove eminently satisfactory as a reference station 
for a number of harbours in its region. 
The comparisons with the principal stations are obtained by 
means of a small type of registering gauge, kept in operation for three 
or four months at secondary stations in the region. The object of 
these comparisons is two-fold; to obtain a tidal difference with the 
principal station, and to ascertain the limits of the region which can 
be referred to it. If the difference in the time of high and low water 
proved to be constant, it was accepted as satisfactory. Otherwise, 
further comparisons were required with other principal stations, or 
the variation in the difference itself had to be reduced to some law 
for calculation purposes. A great deal of such trial work can be done, 
without the expense of additional field work. 
The Gulf and River St. Lawrence.—For the main entrance between 
Cape Breton and Newfoundland, by which the tides of the Atlantic 
enter the Gulf of St. Lawrence, a tidal station was established at 
St. Paul island. It was found possible to refer to this station all the 
harbours on the Gulf coast, in Nova Scotia, Prince Edward island and 
New Brunswick. The gauge at this station was braced between the 
rocky cliffs, and it has been very difficult to maintain. It was twice 
carried away, but it was re-established; as comparisons showed that 
the nearest harbours on the Cape Breton and Newfoundland coasts 
were not suitable as reference stations to command this main entrance 
to the Gulf. 
On the Lower St. Lawrence three stations were established; at 
South-west Point, Anticosti, to command the entrance to the estuary; 
at Father Point, in the middle of the estuary itself; and at Quebec. 
An endeavour was made to deduce tide tables for Father Point from 
Quebec by means of variable differences (12). The variation proved so 
complex, however, that Father Point was raised to the rank of a prin- 
cipal station. It was also found that all the open estuary of the St. 
Lawrence, as well as Chaleur bay, could be referred to it with much 
better advantage than to Quebec. On the other hand, the difference 
between the Anticosti station and Father Point was so constant that it 
could be dispensed with as a port of reference. The remaining region, 
from the Traverse to the head of tide water at Lake St. Peter, is re- 
ferred to Quebec. 
A Paper contributed to the Royal Society explains the character 
and progress of the tide from the open Atlantic to Quebec. It is 
illustrated by a set of simultaneous tide curves from the series of 
stations above referred to (13). 
Bay of Fundy.—St. John, N.B. was found satisfactory as a refer- 
ence station for the whole bay and also for its approaches as far as Cape 
