ANNIVERSARY ADDRESS OF THE PRESIDENT. XXXl 



and with such a force and determination that they could not be turned 

 aside by the numerous projecting bosses of soUd rock on which they 

 have so effectively engraved the record of their transit ? According 

 to the hypothesis which we shall probably all be ready to adopt, the 

 more elevated parts of the Scandinavian range must, at the period we 

 are referring to, have formed an island, round which ordinary ocean- 

 currents may possibly have passed in any direction ; but the notion 

 of such ordinary currents diverging in such various directions ra- 

 diating from the central portion of this Scandinavian island, can only 

 be spoken of as an absurdity. And yet no other force has ever been 

 suggested, or is perhaps conceivable, except that of currents, as effi- 

 cient to drive large icebergs or a mass of looser materials in a deter- 

 minate direction, in defiance of numerous opposing obstacles. It 

 appears to me, therefore, that we are driven to the alternative either 

 of rejecting all theory on the subject, or of adopting that which 

 would attribute these currents to waves of elevation, resulting from 

 frequent, sudden, but not extensive vertical movements of the cen- 

 tral range of elevated land ; movements which we may conceive to 

 have been thus repeated while the mean movement of the whole re- 

 gion was one either of gradual depression or of elevation. 



And here I would make an observation which may not perhaps be 

 without its theoretical value. Adopting this view of the subject, we 

 may conceive the centres of the elevatory movements to have been 

 different at different times, and consequently the directions of the 

 corresponding currents produced by them to have been different, as 

 in fact they would appear to have been from the different directions 

 in which the transported matter has been driven from the same ori- 

 ginal site. But the movements which would send forth the greatest 

 quantity of floating ice would be those which more immediately 

 affected the line of coast ; and the coast being deeply indented, as it 

 must have been, by the present river-valleys when submerged, tor- 

 rents would be simultaneously discharged from their mouths which 

 would determine in a material degree the resulting current in the 

 open sea ; and since these valley-currents would necessarily have al- 

 ways the same directions, they would tend to impress approximately 

 the same constant direction on the resulting ocean-current, whatever 

 might be the precise centre of the elevatory movement. This influ- 

 ence however would, of course, be principally felt at points least re- 

 mote from the then existing coasts. 



When we pass to the great field of northern drift which the con- 

 tinent of North America presents to us, it is not perhaps without 

 some feeling of disappointment that we find the directions of the striae 

 and those of transport without any distinct character of divergency 

 either from local centres or from a general one. The observations 

 described in Dr. Bigsby's paper on the "Erratics of Canada," were 

 made before the importance of striated and pohshed rocks had been 

 recognized, or we should doubtless have obtained much valuable in- 

 formation respecting them from so careful an observer. We learn 

 however from the American geologists that the striae preserve an ap- 

 proximate parallelism in a north-westerly and south-easterly direc- 



