GEOLOGY OF NORTH GIPPSLAND, VICTORIA. 5 
bank is composed of alluvial deposit, and is timbered almost to 
where the end finishes off in a clump of reeds; the width of these 
natural embankments, which separate the waters of the Mitchell 
River from Jones’s Bay on the north and Eagle Bay on the south, 
does not, on the average, exceed ten chains. 
I believe these banks have been formed partly by the ploughing 
action of the floods in the soft deposits at the mouth of the river, 
and partly by the deposition of sediment carried down where the 
current is checked by the reed-beds, and also by similar causes 
whenever the floods rise over the bank itself. 
I have reason to believe from personal observation, as well as 
from information derived from beatmen, fishermen, and others 
navigating the lakes, that these great expanses of scarcely more 
than brackish water are extremely shallow, and are only navigable 
in the deep channels which traverse them. ‘These, it seems to me, 
foreshadow future river-channels so soon as the lakes shall have 
been silted up by the river-deposits or laid dry by further gradual 
elevation of the coast-line. 
It seems to me that we see in these lakes and in the channels 
through them the former condition of the river-valleys, and that the 
present courses of the rivers are probably not due so much to the 
erosion by them of channels in the alluvial bottoms of the valleys 
as to their still flowing in channels which were formed under 
estuarine or lacustrine conditions *. 
The rivers of Gippsland are liable to frequent floods, which are 
due either to heavy rains, generally from the eastward, or to the 
melting of snow accumulated during the winter months on the 
mountains, or to both causes combined. 
During the past five or six years these floods have been excep- 
tionally frequent and severe. Neither the oldest white settlers nor 
the oldest aboriginal natives remember floods of like frequency or 
magnitude. 
I have observed during the time mentioned that the beds of the 
torrent portions of the rivers appear to have been deepened, as in 
the upper waters of the Mitchell, Nicholson, Tambo, or Buchan 
rivers. The course of the rivers in the flat country has been com- 
pletely changed within certain limits, as at Stratford and Bruthen. 
In steep mountain country the hillsides have been stripped of soil 
to the level of high-flood mark, as at the Turnback crossing of the 
Snowy River. Large trees which stood on islands have either been 
torn down and swept away, or stripped of their bark by drifting 
timber. All these various effects 1 have specially noticed in the 
Deddick River. 
The amount of deposit carried down by these rivers is, of course, 
* Mr. R. Brough Smyth informs me that he has detected in Western-Port 
Bay that a divide of mud separates the head of the east and west channels, and 
that this is obscured when the tide is up. We may have probably here the 
commencement of such channels as are a marked feature in the Gippsland 
lakes. 
