1. THE WORK IN TIMBER PHYSICS IN THE DIVISION OF 



FORESTRY. 



BY FlLIHKRT KOTH, 



Late Assistant in the Itirision of Forestry. 



HISTORICAL. 



As in the case of other materials, exact investigation of the properties of wood did not begin 

 until the latter part of the eighteenth and the beginning of the nineteenth century, when Girard 

 linll'on and Dnhainel du Monceau in France, and Peter Barlow, the nestor of engineering in 

 Kngland, laid the foundation for this inquiry by devising suitable methods and working out 

 correct formula' for the computation of the results. As might be expected, the results of this 

 pioneer work, particularly that of the French investigators, were often contradictory, and have 

 to-day little more than historical value. 



Subsequently our knowledge of wood in general, and that of European species in particular, 

 was increased by a number of experimenters. Among these, Chevandier and Wertheim in France, 

 and Nordlinger in Germany, stand out conspicuous. Unfortunately, their apparatus was crude 

 and, in the case of the French workers, the series was too small to satisfy so complicated a 

 problem, while Nordlinger was obliged to content himself with small and few specimens, owing to 

 a want of proper equipment. 



In England considerable money was expended from time to time both by Government and 

 private enterprise, but the eagerness of making the matter as practicable as possible led, unfortu- 

 nately, to much testing of large sizes and to the employment of insufficient (because unsystematic) 

 methods, so that such extreme experiments as those of Fowke and others have really neither 

 furthered science nor helped the practice. In this country the engineering world for a long time 

 relied largely on the results of European testing, and the wood consumers in general depended 

 on a meager accumulation of experience and crude observation concerning most of the fine array 

 of valuable and abundant kinds of timber offered in our markets. 



Ignorance and prejudice had their way. Chestnut oak was pronounced unfit for railway ties, 

 and thus millions of logs were left rotting in the woods, though this prejudice had not a single 

 fair trial to support it. " Bled" longleaf, or Georgia pine, was considered weaker and less durable, 

 millers and dealers were obliged to misrepresent their goods, causing unnecessary loss and litiga- 

 tion, and yet there existed not a single record of a properly conducted experiment to substantiate 

 these views. Gum was of no value, Southern oak was publicly proclaimed as unfit for carriage 

 builders, and the views as to the usefulness of different timbers were almost as numerous as the 

 men expounding them. 



The engineering world was the first to realize this deficiency, and men like Hatfield, Lanza, 

 Thurston, and others attempted to replace the few antiquated and unreliable tables of older text- 

 books by the results performed on American woods and with modern appliances. 



In addition to these efforts of engineers, Sharpies, under Sargent's direction, in his great 

 work for the Tenth Census of 188(1, subjected samples of all our timber trees to mechanical tests, 

 but, since in these tests only a few select pieces represented each species, the engineering world 

 never ventured to use the results. As regards the rest of the wood testing in our country, it may 

 be said that it generally possessed two serious defects: (1) the wood was not properly chosen, and 

 (2) the methods of testing were defective, especially with respect to the various states of seasoning, 

 wood being tested in almost every state from green to dry, without distinction. This is the more 

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