DEFECTS IN TIMBER AND GENERAL NOTES 289 



centre ; in one case it may be only a single line, in another 

 something like a cross, and where there are several 

 radiating from the heart of the timber it is called a star- 

 shake (Fig. 43). They are usually found at the butt 

 end. 



All timber is more or less subject to seasoning checks, 

 or " opening out " as it is called when drying ; some much 

 more than others (Fig. 44). It will be noticed that season- 

 ing checks run from the 

 outer sides towards the 

 centre of the log, just the 

 opposite way of heart- 

 shakes. In elm, Tasmanian 

 blue gum, and other gums 

 they are very common. 

 (See also Figs. 81 and 32.) 



Oak and other hardwoods 

 are very liable to opening 

 at the ends when seasoning, 

 and this is caused by the 

 ends drying quicker than 

 other portions of the timber, 

 and S shaped pieces of iron 

 are often hammered into the 



ends of oak logs to minimise this evil. It is a serious loss 

 for timber merchants when this happens, as it often means 

 that 18 inches or more has to be cut to waste before the 

 timber is saleable. There is a patent in the market, a 

 composition, for coating the timber which is said to be a 

 cure for this evil, but a mixture of whiting and oil is some- 

 times used, and in more valuable -timber a piece of wood is 

 fastened to the ends or they are banded with iron. Opening 

 out on the faces when drying is not, as a rule, serious in fir 

 and pine timber. 



T. u 



FIG. 44. Seasoning checks or 

 " opening out." 



