further iuvcstigation. We know that there are differences in quality, at least for some timbers, in 

 sticks from diiiereut parts of the tree: not only the heartwood differs from the sapwood, but also 

 tbebuttlogfrom thetop log. .,.• ^- • e 



While some experiments would lead us to believe that specific weight is a fair expression of 

 the strength of timber of the same species, yet it would be hazavdoas to rely upon this factor 

 without regard to other physical conditions and structural features of the timber. 



Such "rino-.porous" woods as the oaks and ash show the greatest strength and elasticity when 

 their annual rings are wide, while the slow-gro%vii mountain oak seems to excel in stiffness. From 

 conifers, on the other hand, according to Hartig, the slow-grown timbers seem to exhibit superior 

 quality hence those fi-om rich soils are not desirable. This again has appeared doubtful, or at 

 least true only within unknown limits, from Bauschiuger's experiments, who showed that tensile 

 strength in pines was independent of the total width of the annual ring, but dependent on the ratio 

 between the spring wood and summer wood. 



That wet soil produces brittle, dry or fresh soil tough timber, is believed but needs proof. Con- 

 trary to general opinion, the time of felling seems to be without influence on the strength of pines. 

 The degree of seasoning, on the other hand, seems to increase the strength, although it would 

 still have to be found out whether the manner and rapidity of seasoning may not change this 

 result. Toughness or capacity for bending without rupture, on the contrary, is claimed to be 

 inversely proportionate to seasoning. 



Carriage-makers claimed " that the white oak when grown in the South loses its peculiar tough- 

 ness by which it excels in the North." We have shown by actual tests that this is not the case, 

 and claim the exact opposite from physiological reasons. 



ABSTRACTS OF LETTERS. 



The following abstracts of letters from engineers, scientific societies, and others, regarding 

 the timber studies and tests instituted in the Division of Forestry, received by the Department of 

 Agriculture, are given in this connection as showing the interest manifested in the subject under 

 consideration. The high professional standing of the writers, together with their strong expres- 

 sions regarding the importance and value of the investigation and the diversity of interests 

 involved in this work, form the best argument that could be given for the need of the investigation. 

 For ease in following the arguments adduced, the letters have been grouped under general head- 

 ings in italics expressive of the main ideas therein contained. 



(IJ The information now available regarding the value, properties, and adaptations of our tini- 

 hers is scanty in amount and unreliable in character. 



O. Chanute, consulting engineer, president Am. Soc. C. E., Chicago, 111.: 



As a civil engineer of some forty years of practice I have become aware how little is really known concerning the 

 conditions under which the best results can be secured from commercially useful timbers, and I am glad that your 

 Department has begun its investigations with the southern pines and o.ak8, which must hereafter largely be drawn 

 upon to supply the place of similar woods now being exhausted in the North. The value of such investigations 

 depends so largely upon the competency of the men who are intrusted with them that it was undoubtedly wise for 

 Congress to start with a small appropriation, so that something might be known of the probable results before 

 expending any considerable sums. From my personal knowledge, however, of the thoroughness of Mr. B. E. Feruo w, 

 and Prof. J. B. Johnson, of St. Louis, I am convinced they will accomplish valuable results, and I hope you wiU 

 recommend sufficient appropriation by Congress to enable us to know within a year what practical results are to 

 be expected from the investigation. I, for one, shall be very glad to place at the disposal of your Department, 

 without charge, any information which I have thus far gathered, and I think that the experience gained by those 

 who have handled certain classes of woods, for certain purposes, will be also fieely at youi disposal. 



