106 



ROUGH CONVERSION. 



prominent knots, and other excrescences, &e., should he cut through 

 and exposed ; when straight pieces are required, all irregularities 

 should be adzed off. 



VI. — The bark may be removed by heating it with the back of 

 an axe or with a special tool {Fig. 51), which is also useful when 



Fig. 51. 



Tools/or stripping the bark off logs. (After Gayer). 



the bark has to be taken off only along certain lines, as described on 

 page 23. The immediate removal of bark is a great protection 

 against insects ; but, on the other hand, in hot dry weather it leads 

 to too rapid drying, and consequently to extensive splitting and 

 cracking, unless the timber is worked up within a few weeks, or 

 sometimes even days. Teak poles have, however, been known to 

 remain free from insects throughout an entire rainy season if fully 

 exposed to the rain, and then the dry bark has readily come off 

 like a loose jacket, giving no chance to insects. 



VII. — If the logs are to be carried over long distances by land 

 before being sawn up, it will generally be found advantageous to 

 rough-square them (convert them into balks). The procedure is 

 as follows : — Having fixed the log firmly and in a convenient 

 position for work and for obtaining from it the largest balk it can 

 yield, the workman traces on the section at the thicker end, with 

 the aid of a plummet and line and a carpenter's square, the lines 

 of the four faces to he hewn (Fiff. 52), Then, with a cord steeped 



Fig. 52. 



Mode of rough-stiuari7ig logs. 



in water in which pounded charcoal or red hEcmatite has been 



