APPENDIX. 



379 



In doing this, tlie whole art consists in placing obstruc- 

 tions to the current and waves, so that whatever deposi- 

 tion takes place at high- water, or at the beginning of the 

 flood-tide, when the water is nearly still, may not again 

 be raised and carried off. 



Notwithstanding this accumulation, and also the pre- 

 vention of further waste of the superior carse, the deep- 

 ening of the Tay Firth, formerly carse, and of the gorge 

 at Broughty Ferry, seems still in progress, and could not, 

 without very considerable labour, be prevented. In the 

 case, however, of the sea-basin of iMontrose, a little la- 

 bour, from the narrowness of the gorges, would put it in 

 a condition to become gradually filled wdth mud. Not a 

 great deal more expenditure than what has sufficed to 

 erect the suspension-bridge OA^er its largest outlet, would 

 have entii'ely filled up this outlet, and the smaller outlet 

 might have been also filled to within several feet of high- 

 water, and made of sufficient breadth only, to emit the 

 w^ater of the river, which flows into the basin. The 

 floated sand and mud of this river, thus prevented from 

 being carried out to sea, would, in the course of years, 

 completely fill up the basin. 



From some vestiges of the upper carse, as well as of 

 the lower or submarine carse, in situations where their 

 formation cannot easily be traced to any local cause, it 

 seems not improbable that the basin of the German sea 

 itself, nearly as far north as the extent of Scotland, had 

 at one time been occupied with a carse or delta, a conti- 

 nuation of Holland, formed by the accumulation of the 



