1889.] ^^* fHaupt. 



theory. These changes occur in the same direction through a cycle of years, 

 and are clue to the relation between the flood and ebb forces. The flood 

 resultant, by its constant encroachments from the same direction, trespasses 

 upon the path of the ebb, crowding it over towards shore, and filling its 

 bed, until it is no longer able to find an escape in the old path, when, 

 aided perhaps by a storm, it will break out in a new channel, only to be 

 returned after a series of year^ over the same ground. If these changes 

 were due to storms only, they would be far more variable, and, in the 

 interval between storms, they would be comparatively permanent. The 

 channel would be thrown to the southwest by a north-east storm, and to 

 the north east by one from the opposite quarter, when equally exposed, 

 and there they should remain until again disturbed by this violent action ; 

 whereas such is not the rule. 



The changes at Beaufort and all other places are readily explained by 

 the influence of , this unceasing flood resultant, modified only temporarily 

 by storms. 



The reason why the storm-wind theory is the accepted one, is doubtless 

 due to the fact that the eff'ects are, for the time being, more manifest to 

 the superficial observer, whilst those of the flood component are imper- 

 ceptible excepting after the lapse of considerable time. The effect may be 

 likened to the slow growth of an organic body, not visible to one watch- 

 ing it constantly, but very apparent to one who makes examinations at 

 long intervals. The storm winds, it will be seen, are not ignored by me, 

 but are merely relegated to their true position of secondary agencies, 

 which may co-operate with or oppose the forces of the flood tide. 



In consequence of this cyclic movement it is evident that it would be a 

 mistake to assume that all the ebb channels should remain flexed in a cer- 

 tain direction along one flank of a bay and in the contrary direction on 

 the opposite flank, as some have supposed must result, or that the changes 

 would occur simultaneously at all places. 



The Board continue : 



"Nothing which Prof Haupt has advanced suggests that his tidal cur- 

 rent should be substituted as the 'controlling' or even as an important 

 element in our ocean bar formation. The observed effects may be ex- 

 plained quite as well by the accepted wind-wave theory. Indeed, the 

 fact that such bars abound on shores where no sensible tidal waves exist, 

 proves that no new theory need be invoked." 



The first part of this statement has already been answered, and if the 

 last part were irrefutable the theory would be untenable. But since like 

 causes must produce like effects, if the observed effects are found on tide- 

 less shores, we must expect to find the same causes — and so we shall. 

 Whether the motor be universal or terrestrial gravitation, the agency is 

 primarily a wave of oscillation which in shallow water becomes a wave of 

 translation, breaking generally obliquely upon the shore and producing a 

 resultant movement along the beach. It is a well-known fact that on the 



