9 Dec, 1907.] 



Grading and Levelling. 



709 



construct the needed distribution works. From the outlet in the main 

 supply channel, a distributary channel has to be made with minor dis- 

 tributaries depending upon the area, slopes and other conditions. If 

 these are of large size the buckscraper may again be called upon, or if 

 the ground be light and sandy, the Perkins scraper will do the best work. 

 In ordinary cases, the V-shaped scraper, delver or crowder is the 

 implement. 



The bed of the channel must first be ploughed for its full width, and 

 the scraper is then run along, the lighter and shorter plank acting as a 

 mould-board, pushing the loosened earth to one side to form a bank. Bv 

 running in one direction only, the earth may be placed all on one side; bv 

 alternating, both banks may be made. Channels 2 ft. 6 in. deep with 

 banks of 2 feet in height may be made in this way ; but, of course, 

 without any berm or cess from the edge of the cutting to the toe of the 

 bank. The channel is in fact V-shaped, like the implement making it. 



GENERAL A"1E\V 



WERRIBEE SEWAGE FARM. 



The drawings very fully show the method of construction while a very 

 little experience will teach its use. The mould plank or lighter board, 

 may with advantage be hinged just behind the extension arms, if working 

 in crab-holey country. The timber is preferably redgum, on account of its 

 weight and resistance to hard usage. The delver may be made in any 

 size although that figured is the most generally useful. The strength 

 of team required will of course, vary with the work. In light ground 

 three horses will work the figured size; but generally four will be wanted. 

 Rougher implements may be fixed up to do serviceable work, the original 

 type being merely a forked tree or sapling, adzed down to sometliing like 

 shape and protected here and there with pieces of iron. 



