THE ESKERS OF NOVA SCOTIA. PREST. 393 



6. By examination of the line of deposition to discover 

 some trace on the surrounding drift of the great erosive power 

 of a stream supposed to have flowed under a tremendous 

 pressure as in a subglacial channel. 



7. By examination of the gaps and kames interrupting 

 eskers to find out if they are merely reformed eskers, or places 

 in which there never was an esker. 



