Tidal Phenomena of Hobson's Bay. 1 65 



of height, consequently, even if there had been no flood- 

 waters from above, there must have been a flood (or unusual 

 tide) in the Yarra from the flow of waters up the river 

 meeting and checking the ordinary outflow of the river 

 waters ; but when, in addition to the ordinary river dis- 

 charge, there is the extra drainage due to unusual rain fall 

 and consequent heavy floods, the submerging of the low 

 lying lands becomes a matter of course. 



The obstruction in the river, from the falls and the several 

 bridges opposite Melbourne, aggravates the mischief. Even 

 the iron bridge at Church-street, Richmond, is insufficient to 

 pass the flood- waters efficiently, as shown by the thorough 

 scouring away of the carriage road under the bridge. The 

 result, in the case of the Church-street Bridge, is strong 

 evidence of the very large sectional area requisite to dis- 

 charge the flood-waters of the river, and that it will be 

 unwise, under any circumstances, to construct any bridge 

 lower down of a less span or water way than the Church- 

 street Bridge. Nor do I think it will be wise under any 

 circumstances to reconstruct any dams or weirs in the river 

 between Dight's Mills and the mouth of the river, for they 

 will act in each case as serious obstructions to the free flow 

 of the flood waters. 



After a full consideration of the question, taken in con- 

 nection with the tidal phenomena of the Bay, I believe that 

 effectual means cannot be adopted to permanently benefit 

 the low-lying lands, which do not provide for embanking 

 and raising such lands, as the most prominent feature of the 

 scheme. 



The report of the Commission appointed some months 

 back to inquire into the subject, appears to me to embody 

 nearly all that can be said on the subject, even to the pro- 

 posed point of discharge into the Bay. To one part of the 

 report only do I take exception, and that is, the proposal 

 to reconstruct stone wens across the river above Prince's 

 Bridge. Such weirs would merely change the locality of a 

 portion of the evil, instead of remedying it ; and I submit 

 that the expense involved in the construction of such works, 

 would be more beneficial if employed in buying up the 

 vested interests, which it is one ostensible object of the 

 weir to conserve, namely, the fellmongers and- other offensive 

 establishments situate on the Upper Yarra. 



The construction of the weirs can scarcely be deemed an 

 integral portion of the scheme, and may have been made in 



