So'ine Common Hardwoods. 409 



lience a good deal of doubt is thrown upon the advisability of 

 artificial seasoning on a large scale. Temperature and Circulation 

 of Air are the two main factors in seasoning. But in the manner 

 in which green timber is stacked in the timber yards there is no 

 circulation of air in the stack, and hence drying can only go on 

 from the ends, and these tend to crack badly. As timber dries 

 by diffusion, then in such a stack the moisture must diffuse out 

 from the ends, and hence it is no Avonder that hardwood is said 

 to be a slow timber in drying. If timber be filleted in the stack, 

 that is if cross pieces are laid, some distance apart, across each 

 layey of timber, and the next layer stacked on these, then there is 

 an opportunity for circulation of air, and the winds would be 

 responsible for this. 



A stack of 6 fts. of 6 x 1 Mountain Ash was made in the 

 laboratory, and fillets were placed between each layer. The boards 

 .are drying rapidly, but are not yet finished. The full results 

 will be given in a paper to be published later, when a further test 

 has been made outside with a larger stack. 



The boards have dried rapidly, and a typical case is given 

 TdcIow : — 



Date. 



9.11.18 



29.11.18 



16.12.18 



8.1.19 



20.1.19 



It will be seen that in two months the timber lost 41.2 %, and 

 this must be regarded as very satisfactory. 



During the summer and autumn Melbourne has ideal conditions 

 for natural seasoning if the timber be properly stacked. 



To be able to get the moisture content of timber readily is 

 important, and Professor Laby suggested there might be a relation 

 l^etween moisture content and electrical resistance. The present 

 method of finding tlie moisture content is not. readily available for 

 commercial use and therefore some simple method is necessary. 

 The resistance was measureil by a Megger. It was found necessary 

 to plane up the surfaces of the timber to be tested, as the dry 

 exposed faces greatly increased the resistance. The results are 

 given in Fig. 7. 



Weight. 



Percentage Lost. 



161b. 6oz. 







111b. 2oz. 



32.1 



9 1b. 14 oz. 



39.7 



91b. 10 oz. 



41.2 



9 lb. 10 oz. 



41.2 



