434 WOOD-DEPOTS. 



parts of the depot, they again unite into main canals, and 

 these rejoin the main tioating-c-hannel. In such cases, the 

 floating wood and water are distributed, and the pressure on the 

 shiice-gates and gratings, with which each side-canal is pro- 

 vided at its inlet and outlet, is as slight as may be. In order to 

 attain what is desirable in this respect, and avoid fracture of the 

 booms and other calamities from floods, the main canals, and 

 sometimes the floating stream itself, are provided with outlets. 

 The best and largest river-depots, such as those which supply 

 wood for salt-mines in the Alps, are constituted on the principle 

 of leading the floating wood out of the main stream and dis- 

 tributing it as much as possible in the difl'erent basins of the 

 depot, so as to reduce pressure on the booms and save manual 

 labour in landing the wood. As an example, the newly-con- 

 structed river-depot at Thalham, near Munich, may be cited 

 (fig. 257). Firewood is floated down the river Mangfall to the 

 boom (a), and hence by a side-cut into the reservoir, where the 

 wood is collected in a preliminary manner. The reservoir has 

 two outlets (m, m) as a protection against floods; at h are two 

 canals, each provided with booms and sluice-gates, leading to the 

 basins (7 and II), where the wood is received. The basins are 

 entirely surrounded by solid earth-dams faced with masonry, 

 paved with stones, and provided at their entrances and outlets 

 with sluice-gates. At the end of the basins are gratings, through 

 which, after opening the sluice-gates, the superfluous water can 

 pass through the outlets (c, c) back into the river Mangfall, 

 leaving the wood behind the grating. By this arrangement the 

 current and the floating wood can ho conducted into either basin 

 until it is full of wood. In a few hours, owing to the sloping 

 nature of the bottom of the basins, all the water can be with- 

 drawn through r, and the wood left stranded. It can then be 

 split on the spot, and removed in a perfectly dry state. The 

 firewood thus stored in either basin can be conveyed to ^Munich, 

 as rcfjuired, by the adjoining railway. 



Fig. 259 represents the arrangement of the river-depot at 

 Traunstein ; it is constituted on the same general plan as that 

 at Thalham, but is distinguished from it by the more elaborate 

 protection afforded against floods and silt. The floating-channel 

 {K, a, h) is cut ofl" from the river Traun by a lateral boom ((/, b) 



