ZHl WATER-TKAXSl'OKT. 



to carry-out, that frequently the wood is lamlcd and passed down 

 a water- sHde and phiced again in the stream further on. 



Careful pavin^,' of the bed of a stream is not unfrequent at 

 openings from tanks, and to a certain distance inside the latter. 



iii. Rectify ituj ihe Float! iKj-CJiaiuicl. 



The channel of a mountain-stream usually winds consideraLly 

 as soon as it approaches the plain, and its current is thus 

 considerably reduced. The wood which is being floated has 

 therefore to travel far, in order to pass over a comparatively 

 short distance, and may become water-logged. Owing to the 

 slight fall, inundations occur with every high water, and the 

 banks of the stream are injured and much wood stranded far 

 and wide. 



Straightening the channel of the stream is then the best 

 mode of obviating these dangers. The stream is straightened 

 by making short artificial cuts between its bends and windings. 

 Such a cut is generally commenced at several places between the 

 points on the stream which are to be joined, the banks then 

 serving as dams, until the channel is completed. It may even 

 in such cases be worth while to make tunnels for the water to 

 pass, as at Hals, near Passau. 



Artificial floating-canals leading to a timber-depot are of the 

 same nature as the above, and sometimes run from one river- 

 basin into another. 



The best known of these artificial floating-canals is that 

 belonging to the Prince of Schwartzenberg, at Krummau, in 

 ]3ohemia ; it is 35 miles long, of which GOO yards are tunnels 

 leading from the centre of the forests to the river Miihel, 

 which flows into the Danube between Lintz and Passau, and 

 brings down the yield of 35,000 acres of forest. 



"Whenever a canal is dug, levels must be most carefully taken 

 beforehand ; one in fifty is the best fall, though frequently 

 unattainable. The canal just described has a fall of one in 

 nine for a short distance, and one in the Bavarian forest a fall 

 •of one in five. In such places, the bed of the canal must be 

 leaved, or terraced, as already described. 



In the latter case, the upper section of the canal is only 4 



