386 THE TIMBERS OF THE WORLD 



hand, suppliers of the drying plant were commercial firms who, when they 

 had accomplished, as the American contracts state, " shipment in sixty 

 days," went no further ; while, on the other hand, users of timber were 

 satisfied if they had successfully dried the several kinds and sizes of timber 

 used in their particular manufacture. As a general rule, however, 

 artificial seasoning was only employed as an emergency measure, or 

 because it was impossible to procure naturally seasoned wood. 



One of the greatest hindrances to development was the fact that 

 artificially seasoned timber was not knowingly accepted for Government 

 contracts, and rarely for private ones. The word " knowingly " is usee 

 ad^dsedly, because enormous quantities of imported timber which hac 

 undergone the process in other countries were accepted, but the contractor 

 was not permitted to use timber which had been artificially seasonec 

 on his own premises. The use of primitive and harmful processes bj 

 people who for various reasons found themselves unable to accept the 

 latest, and perhaps somewhat expensive plant, produced some bad 

 results. Again, where better methods were employed, their operation 

 was too irregular to be efficient, and the results were not encouraging. 

 Thus artificial seasoning has been condemned by those who knew of its 

 frequent failure, but who did not know that such failure was the fault, 

 not of the process itself, but of its indifferent application. All 

 engineering materials except timber lend themselves to rigid tests and 

 graduations. So great, however, are the variations in the grades of 

 timber, that it has hitherto been considered impossible to find any 

 satisfactory series of tests for regular application. Timber is a natural 

 product, and not a manufactured article. A piece produced by one tree 

 or of one species may differ considerably in quality and strength from a 

 piece of a similar species growing within a few yards. Indeed this may 

 vary greatly in different portions of the same tree. Nevertheless, 

 scientific tests can be used with advantage in grading timber even if 

 less strictly than in the grading of steel, for instance. It is found that 

 the facts and figures obtained show regular and consistent results, while 

 an examination of the material thus accumulated proves the advantage 

 of such tests. It becomes clear that it is possible and of much value to 

 calculate the resistance under stress in the case of timber, upon the same 

 principles as it is calculated in the case of other structural materials. 

 It is only necessary to make allowance for wider variations. This margin 

 of variation can, however, be materially reduced through artificial 

 seasoning, which makes possible a more careful and reliable grading. 

 What is yet needed is a series of comparative experiments which shall 

 test wood naturally seasoned and wood artificially seasoned, so that the 

 results of the two processes may be compared and some conclusive 

 facts obtained. 



