30 



The logs are shipped to the test hiboratory at St. Louis, iu charge of Prof. J. B. Johnson, and are 

 there sawed and prepared for testing, carefully marked, and tested for strength, as described fur- 

 ther on. Up to the time of writing some twenty-six hundred tests have lieen made. 



The fact that tests on large pieces give different values from those obtained from small pieces 

 being fully estabhshed, a number of large sticks of each species and site will be tested full length in 

 order to establish a ratio between the values ol)tained from the different sizes. Part of the material 

 is tested green, another part when seasoned by various methods. Finally, tests which are to 

 determine other working qualities of the various timbers, such as adapt them to various uses, are 

 contemplated. 



I consider it my duty to state here that through the energy and devoteil interest of Professor 

 Johnson alone has it been possible to carry this work into execution, since he provided by personal 

 and private endeavor the entire outfit of the test laboratory, and with much financial risk organized 

 the testing work. 



The disks cut from each log and correspondingly marked are examined at the botanical labora- 

 tory of the University of Michigan, at Ann Arbor, by Mr. Filibert Koth, who has prepared himself 

 for this work, requiring great care and painstaking, by several years' preparatory studies. An 

 endless amount of weighings, measurings, countings, computings, nucroscopic examinations, and 

 drawings is required here, and recording of the observed facts in such a manner that they can be 

 handled. Chemical investigations have also been begun in the Division of Chemistry of the Depart- 

 ment of Agriculture, the tannic contents of the woods, their distribution through the tree and their 

 relation to the conditions of growth forming tlie first series of these investigations. 



It is evident that in these investigations, carried on by competent observers, besides the main 

 object of the work, much new and valuable knowledge unscmght ibr nnist come to light if the 

 investigations are carried on systematically and in the comprehensive i)lan laid out. Since every 

 stick and every disk is marked in such a manner that its absolute position in the tree and almost 

 the absolute position of the tree itself or at least its general condition and surroundings are known 

 and recorded, this collection will be one of the most valuable working collections ever made, allow- 

 ing later investigators to verify or extend tlie studies. 



Although the work as now organized has been carried on for hardly a year, the niunber of 

 definite problems which present themselves and are destined to be solved by it is quite astonish- 

 ing. Besides the general examining and testing species by species, tliere become, therefore, neces- 

 sary special series of investigations. For instance, the inlluence of seasoning on the strength of 

 timber will form such a special series presently to be undertaken. The influence on the quality 

 of the wood of tapjang the Southern longleaf ])ine for turpentine is a series on which we are now^ 

 engaged, and a brief resume of the most important results of which has been i)ublished. 



The influence of the length of service upon construction members will form another series as 

 material can be obtained. Altogether there is o])ened up an almost endless field of useful work, 

 the richest mine of unexplored knowledge, the importance of which can hardly be overestimated, 

 for after all, though we in the United States are slow to realize it, wood is our most important ma- 

 terial of construction, and increased knowledge regarding it must aftect, directly or indirectly, Q\ory 

 conceivable interest. 



By and by it is expected that the number of tests necessary may be reduced considerably, 

 when for each species the relation of the diflerent exhibitions of strength can be suflnciently estab- 

 lished, and perhaps a test for compression alone fiu-uish sufficient data to compute the strength iu 

 other directions. 



