Reclamation of Batman's Swamp. 11 



occurs ; after this sand is passed, a black retentive clay 

 appears, and continues for at least a depth of 24 feet, but 

 how much further I am unable to say, having only excavated 

 to that depth. 



In order to make the whole of the swamp avadable for 

 cultivation, it will be necessary to embank it on the south 

 and west by an embankment 24 feet wide at the base, and 

 five feet in height, thereby giving a total height of about 

 eight feet above the ordinary level of the Yarra, when the 

 surface level of that river is uninfluenced by unusual causes. 



In the formation of this embankment it is necessary, first, 

 to cut a trench three feet in width through the top soil and 

 the underlying stratum of sand, until the stiff retentive clay 

 is reached ; this would be at a depth of about three feet, at an 

 average. The material thus excavated would form part of 

 the embankment above the surface level. After setting off a 

 distance of 13 feet 6 inches on the inner or swamp side of the 

 trench, I propose to excavate a canal 24 feet wide by 5 feet 

 deep, for the threefold purpose of, first, obtaining the mate- 

 rial to form the embankment ; secondly, to drain the swamp 

 itself; and thirdly, that when partially full it may be used as 

 a canal for the transport of manure and produce, in flat- 

 bottomed barges. Care must be taken that the trench first 

 mentioned is filled up with the stiff retentive clay, excavated 

 from the canal, and that a wall of the same description be 

 carried up in the centre of the embankment to its full height. 



This embankment in its course intersects some patches of 

 the tea-tree scrub, as shown on the plan, which would neces- 

 sarily have to be cut down. This scrub, judiciously used, 

 could be incorporated in the bank, so as to prevent the softer 

 material slipping, and also afford considerable protection to the 

 bank itself, in the event of the river rising to an unusual height. 

 The tea-tree scrub, either in the form of fascines or otherwise, 

 would be used on the river side of the embankment only. 



By referring to the section of the embankment, it will be 

 seen that to make this, the least costly method is to excavate 

 the material upon the spot, and that its construction thus 

 leaves the canal or drain, or both, fit for their intended pur- 

 poses, without any extra expense having been undergone for 

 their formation. 



I also propose to use the sand excavated (or a portion of 

 it) to dress the top of the embankment, so that in all seasons 

 there would be an excellent footpath from the city to the 

 Salt Water River. 



