(4) Eegarding the variation of strength with the height in the tree, it was found that for the 

 first 20 to 30 feet the values remain constant, then occurs a more or less gradual decrease of 

 strength, which finally, at the height of 70 feet, amounts to 20 to 40 per cent of that of the butt log 

 for the various exhibitions of strength. 



(5) In shearing and crushing across and parallel with the grain, practically no ditterence was 

 found. 



(G) Large beams appear 10 to 20 per cent weaker than small pieces. 



(7) Compression tests seem to furnish'the best average statement of value of wood, and if one 

 test only can be made this is the safest, as was also recognized by Bauschinger. 



The investigations into the effect of bleeding the trees for turi)entine leave now no doubt of 

 the fact announced in a preliminary circular, that bled timber is in no respect inferior to unbled 

 timber. 



This conclusion, to which the mechanical tests lent countenance, is strengthened by the chem- 

 ical study of Mr. M. Gomberg into the distribution of resinous contents throughout the trees bled 

 and unbled. These show what physiological considerations would lead us to anticipate, that the 

 resinous contents of the heart wood take no part in the flow of resin induood by the "boxing" or 

 "chipping" of the tree, being nonfluid, and also being found present in larger amounts i)i the 

 heart wood than in the sap wood as well before as after bleeding. The drain appears to be entirely 

 from the sap wood, and as this does not enter into lumber production, being hardly more than two 

 inches on the radius, it may be left out of consideration. 



The result of the tests, to the efliect that bled timber is stronger than unbled, which Prof. 

 Johnson proposes to explain as a result of the bleeding, does not seem to admit of such relcrcuce. 

 It is suspected that the timber from the orchard might have come from a locality the soil coiiili- 

 tions of which were apt to produce better quality, the comparison of bled and unbled timber 

 having been made on material from different localities. 



From the field report of Mr. Eoth it would appear that opinions of practical men are so much 

 at variance as to the effect of bleeding as to be of no special value, and we can claim that the 

 discrimination made against bled timber, be it on account of inferior strength or inferior durability, 

 is due to an unwarranted prejudice. 



Tlie physiological considerations and the processes employed m the gathering of turjicnline 

 in this and otlier (countries will be found fully discussed in the annual I'eport of the h'drcst ry 

 IJivision for the year 1S92. 



The arduous a7id difficult task of collecting the test nniterial in the careful manner required 

 for this work has been performed by Dr. Charles Mohr in a 7nost efficient manner. An ins])cction 

 of tlie field records will give an idea of wliat this involves in the way of selecting, examining, and 

 describing sites and specnnicns, but no idea of the hardships wliich are encountered in tlie ])er- 

 formance of the work of securing and shipping logs and disks. There are now collected, in all, 

 si)ecimens from 233 trees, on twenty different sites, of Pinus jmlustris, echinata, Twda, (^uercus 

 michauMi, rubra, falcata, Phellas, tinctoria, alba, obtusiloba, comprising in all 409 logs and 1,<S.')5 

 disks. 



Thanks are due to the management of the Louisville and Nashville, the Iron Mountain, and tli(! 

 Southern Pacific railways for free transportation of men and materials, without which, in the face 

 of scant appropriations, the x>rogress could not have been as rai)id. 



Eegarding the methods used in analyzing and comparing the results of tests, we are indebted 

 to Mr. William Kent, C. e., for valuable suggestions. The idea of the "average quality" is his 

 own. This, to be sure, does not pretend to be an expression of actual quality, but serves the 

 useful purpose of a practicable ba.#is for arrangement of material for comparison. 



On the whole, the niethods of handling the very large amount of data from mechanical and 

 physical examinations for comparative study have not yet been fully matured and determined upon. 



It is contemplated, wlieu work can be resumed, to study as a separate series tlie influence of 

 various methods of seasoning upon quality, besides extending the mechanical tests to a number 

 of important species tlnit are still imperfectly known in their properties, like the Douglas spruce 

 and the bald cypress. The work will jnogress and results be published in jiroportion to the funds 

 approi)riated for the investigations. 



B. E. Feenow. 



