362 DEPARTMENT OF THE NAVAL SERVICE 



shallowest parts of the banks are thus covered by water of negative temperature. 

 Towards the deeper water the temperature increases very slowly in the channels 

 between the banks, and comparatively rapidly on the outside of Banquereau, where a 

 temperature above 5° C. is reached at a depth of 150m. 



Section IX. Stations 33-36. 



The last section on this cruise runs from station 33, off Cape Breton, to station 36, 

 near the coast of Newfoundland, crossing the Laurentian channel at the outer part of 

 Cabot strait. 



Salinity. — From the surface north of station 34, down to a depth of 60m. near the 

 southern slopes, is a layer of intermediate water stowed up against the south shore. 

 The bank water in the northern part of the section occupies the surface and reache* 

 down to 100-160m. The 33 isohaline has an undulating course, rising as a wave up 

 to 100m. at station 35, and sinking down towards the slopes on both sides of the 

 channel. The rest of the section down to the bottom is occupied by slope water with a 

 salinity of 34.66 Voo near the bottom (400m.) . The 34 isohaline runs at a depth of 

 225-250m., displaying a wave similar to that of the 33 isohaline. 



Temperature. — As in the foregoing sections the surface temperature is very uni- 

 form 4-4.5° 0. At a depth of 30-125m. on the southern slopes, and of 60-115m. 

 on the northern slopes, we find water layers with temperature below zero. These two 

 minima are separated by somewhat higher temperature in the middle of the channel at 

 station 35, and their influence is shown by the course of most of the isotherms in the 

 section, the upper 2° and 4° isotherms running somewhat deeper at station 36, and 

 the lower 2° and 4° isotherms forming waves upwards at the same station. Near the 

 bottom (400tn.) we find a temperature of about 4° C., almost identical with the surface 

 temperature. 



This section confirms the impression mentioned under section III, that the gulf- 

 water forms an outflowing current along the north shore of Cape Breton island. This 

 current seems to be more superficial and its water fresher, salinity from 30-5 ''/oo to 

 about 32 ^/oo, than the water of the inflowing current in the northern part of the 

 channel, which seems to be strongest in depth of 50-lOOm. The outflowing water 

 is thus intermediate water and inner-bank water, while the inflowing water is outer- 

 bank water having a salinity characteristic of the Newfoundland banks. The posi- 

 tions of the two temperature minima in the section seem to confirm this idea about the 

 origin of the superficial layers in the Cabot strait. 



EEVIEW OF THE SPRING CRUISES. 



After this description of the sections made during the cruises in the spring it may 

 be of interest to review the hydrographical conditions in the area investigated. In 

 doing so I may conveniently refer to the section maps constructed by Mr. Sandstrom 

 and given in his report (The Hydrodynamics of the Canadian Atlantic Waters, plates 

 II and IV). 



Salinity (Sandstrom, Plate II), 



Coastal Water {helow 30 Voo). — At the surface, water of this salinity is found in 

 the inner, and especially in the southern part of the gulf, round Prince Edward 

 Island, and in the north out towards the middle of the Esquimau channel. In the south 

 we find the coastal water down to a depth of about 25m. Water of a salinity below 30*^/00 

 must also presumably occur almost everywhere nearer to the coast, and especially in 

 bays with outlets of fresh water. Thus it is certain that the surface water of the Nova 

 Scotian banks oft' the Gut of Canso to some extent consists of coastal water, though the 

 spring cruises did not include this area. 



