6 ROYAL SOCIETY OF CANADA 
date they had only been used in fresh water, and there was much 
difficulty in making them work satisfactorily at sea. By their use, 
however, constant observations could be secured day and night, which 
was essential in dealing with tidal streams which show so much in- 
equality in strength. The velocity of the current was measured at 
the standard depth of 18 feet (three fathoms). This was adopted to 
place the meter below the keel of the surveying steamer when lying 
between wind and weather, and as this depth may be considered to 
be the average draught of an ocean steamer, it thus represents the 
actual effect of the current upon a vessel. The appliances used for 
all the purposes in view are described in the Reports of Progress (3). 
Special attention was also given to the study of the under-current, as 
normal conditions often continue below the surface during times of 
wind disturbance (4). The other observations taken, included the tem- 
perature and density of the water, and meteorological data for com- 
parison with the behaviour of the current. The wind record was 
obtained from an anemometer on board, and the barometric variations 
were registered by a barograph. 
In carrying on the work of the Survey, the surveying vessel was 
anchored at carefully selected stations, and the vessel itself served as 
a fixed point from which to determine the direction and velocity of 
the current. In this way as much information can be obtained in 
24 hours of continuous work, as in a week by running measured 
courses. Interruption from fog is also avoided, as it does not interfere 
with the continuity of the observations. 
INVESTIGATION OF THE CURRENTS. 
Gulf of St. Lawrence.—In the first three seasons, 1894, 1895 and 
1896, a general investigation of the Gulf of St. Lawrence was made. 
The relation of the Gulf area to the ocean was ascertained by obser- 
vations in Cabot strait, between Cape Breton and Newfoundland, and 
also in Belle Isle strait. Similar observations were carried on at the 
mouth of the St. Lawrence, north and south of Anticosti, to determine 
the relation of the St. Lawrence estuary to the Gulf. The temper- 
ature and density of the water were taken throughout the Gulf, which 
proved a valuable means of tracing the general circulation of the water. 
The results of these investigations have been fully reported in the 
Reports of Progress, and they are also summarized in a special pamph- 
let (5). 
It will therefore suffice to note, regarding the results, that no 
currents exceeding one knot were found in the open waters of the Gulf, 
apart from local straits and passages. This in itself served largely to 
dispel the supposed dangers to navigation in these waters. Erroneous 
