388 THE TIMBERS OF THE WORLD 



At the present time the situation is definitely changed. Excellent 

 results have been consistently obtained with enormous quantities of the 

 most difficult timbers, and failure to obtain good results must henceforth 

 be attributed either to an unsatisfactory method or to the inefficiency of 

 the operator. 



Home-grown timber is being more largely used at present owing to 

 the shortage of imported stock, and this will probably be extended when 

 the effects of the new afforestation schemes are felt. On this account 

 the need for timber dryers will become urgent if bad or unstable work is 

 to be avoided, for when the timber has left the saw-miUs it will be used 

 by the builder whether seasoned or not. If the timber is artificially 

 seasoned direct from the saw, the cost of stacking in the dryer merely 

 corresponds to that of yard stacking, and is therefore not an extra 

 expense. The waste from the mill is used to generate the steam for 

 heating the dryer. This reduces the cost of drying to a minimum. 

 Home-grown hardwoods, such as ash, beech, and oak, can be partly dried 

 at the saw-miU, and the seasoning completed at the user's works after 

 cutting to gross finished sizes. Generally, however, large users will find 

 it advantageous to have their own dryers and to buy their timber green. 



In timber-producing countries such as America, Sweden, and Finland, 

 it is the general practice to pass all the planks from the saw through the 

 drying kiln. In America the timber is dried out completely. So treated 

 it is perhaps quite suitable for the very dry climate of that country, 

 but American kiln-dried timber is generally considered " over-dry " 

 in Great Britain. In Scandinavia, on the other hand, the drying is only 

 partial, and is done to reduce the moisture so that the timber can be 

 close piled for shipping, the shipping weight and cost being thereby 

 reduced. Such timber is not ready for immediate use, but requires either 

 air dr3dng for some months or processing in a dryer for about a week. 



One of us (S. F.) had experience with some very large timber dryers 

 in Finland, the size of which may be gauged from the fact that when 

 working on i^-inch thick yellow deal the output of one plant was 60 

 standards per day, that is, 9900 feet cube. These dryers were put in to 

 fulfil the following specification : 



1. To reduce the weight of the wet timber by 30 per cent without 



warping or splitting. 



2. To turn out the dry timber without discoloration, so that it could 



be sold in England and elsewhere as " Guaranteed not kiln- 

 dried." 

 These conditions were fulfilled in all points, and doubtless many of the 

 opponents of artificial seasoning have used quantities of this " guaranteed 

 not kiln-dried " wood with great satisfaction. 



This partial drying is in many ways better than the American drying- 



