Yarra Floods. 151 



of the subsequent operations necessary for removing the 

 sandy deposit at the mouth, the St. Kilda channel appears 

 to me to be worse than the Sandridge lagoon channel. In 

 fact, there are no valid arguments that I can discern in 

 support of the St. Kilda scheme. 



The line of channel proposed in 1853, for a ship-canal, 

 differs materially as regards results from those last mentioned, 

 inasmuch as, if suitable for a flood-channel, it would also be 

 available for giving passage to shipping between the Bay and 

 Melbourne. It is doubtful, however, if an outlet for flood- 

 waters formed at the point at which the entrance to that 

 canal was proposed to be made would be effectual. The 

 tendency of the mouth to choke with silt would be similar 

 to that of the two schemes last mentioned. The argu- 

 ment has been frequently made use of, that because the 

 deep water penetrates more closely into the shore at that 

 point than at any other, the mouth of a canal would be less 

 liable to obstruction from deposit of sand there than else- 

 where. But it mast be recollected that the conditions of the 

 case would be entirely altered if the upland waters emptied 

 themselves through a channel having an outlet at that site. 

 The waters of the Bay driven up by southerly winds, culmi- 

 nate in force at that part of the shore, and coming over the 

 deep waters of the Bay, hold little or no debritus in suspen- 

 sion. It is not surprising that a body of water, free from a 

 mixture of solid matter being hurled against the shore, wave 

 after wave, dming the southerly "winds, gradually eats away 

 the bank of sand formed during easterly winds, and scatters 

 the deposit right and left, to be deposited on the eastern side 

 upon the shore ; and on the western side, to be carried away 

 by the natural currents into deep water. Were an open 

 cutting to be formed emptying into the Bay at this point, 

 the state of the case would be entirely altered. The beat of 

 the waters of the Bay is at present against a solid shore, on 

 which the only effect that can be produced is, the carrying 

 away of the sand to other sites immediately adjoining, or 

 the floating away of the material into deep water. But if 

 the outfall of the Yarra discharged into the Bay at this 

 locality, the results would evidently be wholly different. 

 Then the force of the waters of the Bay during southerly 

 winds, instead of being expended, as now, in breaking fruit- 

 lessly upon the shore, would drive the sand into the mouth 

 of the canal with far greater force than the outward current 

 could resist. At the point where the forces of the out-flowing 



