150 Forestry Quarterly 



ROADS AND SURVEY. 



A well illustrated article by Dr. Fank- 

 Transportation hauser describes the logslides which are 

 in to a large extent in use in the Austrian 



Mountains Alps. Here wood is still relatively cheap 



and branches and tops unsalable. Coni- 

 ferous wood ranges in price between 3 to 9 cent per cubic foot, say 

 $4 to $10 per M ft., hardwoods up to 11 cents. Hence cheap 

 methods of transportation are needed. Moreover, felling areas 

 are concentrated and clearing system alone is in favor. A well 

 planned system of roads, sled roads and log slides, each adapted 

 to the special conditions of topography make profitable utiliza- 

 tion possible. 



The .slides are constructed for permanent use, and so as to 

 bring the logs long distances, 2 to 3 miles without stops, various 

 constructions being combined to utilize the topography. The 

 simplest construction is a simple ground slide improved by lay- 

 ing down, partly buried, "ribs", short logs, obliquely pointing 

 forward, V-shape ; or else laying the ribs horizontally and 

 boom-logs along the two sides. In curves, the inner side is 

 then laid lower, so as to relieve the outer boom. If the grade is 

 insufficient the base of the slide is laid out with logs placed 

 lengthwise to reduce the friction. The width between booms 

 varies usually between 2.5 to 4 feet, and, in the curves, which 

 have a radius of at least 150 to 200 feet, 5 to 8 feet. Broader 

 slides are not desirable because in these the logs are apt to 

 wobble and perhaps jam. One of the described slides passes 

 through a 100 foot tunnel, another through a ditch blasted in 

 the rock ; trestles and bridges are frequent features, and super- 

 imposed and fortified booms, especially along narrow rock hang- 

 ings, etc., and curves. All these features are combined into 

 one homogeneous runway. 



The grade is an important point, but varies within wide limits, 

 up to 60 per cent, and even 80 per cent. , one of the described slides 

 averaging 60 per cent. Such high grades cause a certain 

 amount of loss in the wood, which in this case where the base 

 of the slide had in some parts to be paved with rock to avoid 

 damage by water is calculated at 30 per cent. 



The minimum grade is preferably not under 10 per cent, 

 except where ice roads are utilized. For short portions a lower 



