660 The Tropospheric Circulation 



salinity greater than 35%o. From a large number of individual cases Le Danois has 

 attempted to derive definite rules according to which these trangressions move to the 

 north-east. These instrusions of Atlantic water into north-west European waters are 

 discernible only in their effects on the "continental" water masses over the shelf. 

 Here the warm transgressions at the surface over the continental plateau always are 

 preceded by highly saline transgressions in the deeper layers. The transgressions 

 appeared nearly always to follow the course of the valleys of the submarine relief. 

 The direction of spread is mainly to the north-north-east, so that the speed of this 

 spread of the intrusions is the less the more it deviates from this direction. By following 

 these phenomena in the sea off the coast of France for a large number of years Le 

 Danois has found certain periodicities in the occurrence of the transgressions, which 

 superimpose each other in the same manner as waves. 



However, it appears difficult to follow the Le Danois theory of these transgressions, 

 since he uses several arguments quite contradictory to the established fundamentals 

 of dynamic oceanography (Schubert, 1935). 



