Periodical Literature. 143 



Overhead cableways are particularly useful 

 Use for moving logs and sawn lumber from 



of inaccessible forest regions to drivable 



Cableways. streams or to railroads. Their mainten- 



ance is economical and the cost of opera- 

 tion is low, depending on the fall from the woods to the delivering 

 station. Where the fall is great no power is required and in 

 extreme cases the system may itself become a source of power. 

 A few facts and half-a-dozen illustrations of the use of these 

 cableways in the mountainous countries along the lower Danube 

 are given in a recent number of "Silva." 



A later number of the same periodical gives similar data for 

 the cableway connecting the wooded upper slopes of the Usambara 

 mountains in German East Africa with the plains below. With 

 a slope of 87% in places this is the steepest of its kind in the 

 world. The cableway is used to carry cedar wood and farm 

 products from the higher slopes to the plains below, and manu- 

 factured goods in smaller amounts form the up-going load. No 

 power is required ; on the contrary the system runs a dynamo for 

 furnishing light to the plantations below. 



Zur Prage der Holsgeivinnung im franssylvanischen Alfengebiet. Silva, 

 July I, 1910. Pp. 201-2. 



Die steilste Bahn in der Welt, eine Holstransportbahn. Silva, Novem- 

 ber 4, 1910. Pp. 345-6. 



A novel device to replace axe and saw in 

 Tree felling trees and cross-cutting logs has 



Felling been patented in Germany, and it has been 



Machine. widely described in lumber trade journals 



of that country and this. The cut is made 

 by burning with the heat developed from the friction of a one- 

 millimeter steel wire drawn back and forth across the stem at 

 the rate of 1,500 times a minute. Power is furnished by an elec- 

 tric or gasoline motor set up a hundred feet or more from the 

 tree to be felled. A pair of steel cables runs to the stem to be cut. 

 The ends of these cables have suitable clips for attaching the 

 wire which makes the cut. The length of this wire is about 

 twice the diameter of the stem. A new wire is used for each 

 cut. The cost of these wires is less than one cent apiece. The 

 operation of the felling machine requires one man attending the 

 motor. It is difficult to compare the time required for making 



