384 Drift Ice and Currents of the North Atlantic. 



rations made at different times and places, during the survey, 

 confirmed these results. Hence it appears that the drainage 

 waters received by the rivers were discharged by means of the 

 surface current, which swept over the cold subjacent waters that 

 were brought in by the polar current and the flood tide. These 

 facts should be remembered in viewing the relations of the polar 

 currents to the Gulf Stream. 



In relation to the southern outlet of the Gulf of St. Lawrence, 

 it has been common for navigators and others greatly to overrate 

 the proper river current of the St. Lawrence, in its extension 

 southward of Breton Island and Nova Scotia. This fresh-water 

 current, when compared with the branch of the polar current 

 which joins it through the Strait of Belle Isle, is but of insignifi- 

 cant volume ; and the current through this strait, in its turn, is 

 but an ocean rill, when compared with the great volume and 

 force of the cold currents which pass to the eastward and south- 

 ward of Newfoundland. 



It appears that Rennell was embarrassed in his investigation 

 of the polar currents of this region, by admitting the assumption 

 that a portion of the cold water, eastward of Newfoundland, was 

 caused by the Bank itself. This hypothesis had been sanctioned 

 by distinguished writers, but the observations and facts on which 

 it was founded can now be satisfactorily explained by the admit- 

 ted influence of cold currents, either superficial or sub-aqueous. 

 He appears, also, to have viewed the Gulf Stream as opposing a 

 direct obstacle to the further passage of the polar currents, but it 

 appears to us, that the streams of existing aqueous currents are 

 found intersecting each other, much in the same manner as they 

 would pass through quiet waters, and that they quietly impose or 

 imbed upon each other like as stratified currents of air, or lateral 

 currents from the forks of rivers, are found to accommodate each 

 other, in their respective courses. In these river cases, as apart 

 from the extraneous deflection by the shores, while the original 

 momentum of each stream continues, one of these may be borne 

 away from its original course, and thus be resolved to a new or 

 modified direction by the further progress of the current in which 

 it is imbedded ; but in such cases, a diversion of the course of 

 the lower current does not usually take place. 



In the case of ocean ice-currents which intersect a surface 

 cross current, while the common surface ice conforms more or 



