78 



THE AVHITE PINK. 

 Averatje Hlrfnylh n/ the wood of While Vine of different treen at 12 per cent mointure. 



Locality. 



Original 



number uf 



tree*. 



}b[oillllUHOf 



I'lasticitT I 



(1.000 ! 



I [M>11U(1(»). : 



Bendlug to— 



Rupture. 



Relative 

 elastic 

 limit. 



Coinpnu. 



sion I'lid- 



wi»e. 



I Comprea- { 



Hioii acnws 



gniin to :{ 



per cent de- 



; fomialion. i 



Sbearlnjr 



paratli'l tii 



liber. 



A vcrage 

 BpeeiHr 

 weight. 



\FtAtndtper 



I I Sfj.in, i 



■Wieconsiu Wl j 1,300 8,100 ' 



Do ] 10-.; 1.520 ' 7.400 i 



Do 104 \ 1,:)5ll 7.800 



Do I 112 i.:i:iii S.30I) 



Do 114 1.1911 (ili.SOO 



Do I 110 1. 3.^)0 8,300 



ilicliig.in I OOI 1.3T0 7.40(1 



Do 802 1,470 7.800 



Do 603 1,470 7,8riO 



Wieconsin 0a7 1.380 8.000 



Do 808 1.580 8.0IIU ! 



Do 009 i 1,510 8,200 I 



Average 1,410 7,900 | 6,300 



Avenigc for trees 601 to 809 ' 1,400 8.000 6,700 



Pouniltper Pmindt per 

 tq. in. 

 0, 200 



f:, 300 

 8.000 

 6. 300 

 .'.. 000 

 5.000 

 0. 3110 

 6. 700 

 6. 050 

 0. 800 

 7.450 

 8.700 



Hq, rn. 

 4.600 

 4,200 

 4.800 

 5,000 

 4.250 

 5. 000 

 5.500 

 5,700 

 5.400 

 5, 700 

 5,700 

 6,200 



Poxtndn per 

 tq.in. I 

 690 I 

 560 

 620 I 

 650 

 030 

 560 

 810 

 880 

 790 

 910 

 670 

 880 



Poundn per 



aq. in. 

 400 

 320 

 430 

 440 

 400 

 470 

 350 

 420 

 320 

 340 

 330 

 340 



0.42 

 .36 

 .40 

 .39 

 .36 

 .383 

 .38 

 .37 

 .38 

 .39 

 .38.-. 

 .392 



5.200 



720 



.384 



(I Insnfticient datn lor a fair average. 



In tbe above table the datii for trees 101 to 11(> are iiisufflcient. liotli material ami tests for 

 trees (iOl to 600 were satisfactory in every respect, ami tlie results, therefore, of far greater value 

 than tho.se for trees 101 to IIG. 



Ill keeping' with its greater weight, the wood of the butt logs is slightly stronger tliaii that of 

 the toj) logs, and there is generally a regular dilfereiiee between ditfereiit ])arts of tlie same cross 

 section, the center, as appears usual iu pine, being the weakest, the heavier intermediate portion 

 the strongest, and the peripheral part lying between the two. 



For a more careful study of this relation, tests were made of a set of L' by 2 inch sticlcs cut out 

 of one log from eaeli of three trees, in such a manner that the centers of the logs formed one set, 

 the part midway from center to bark another set, and the outer portion of the logs a third or outer 

 set, the latter two being all quarter-sawed pieces. The tests furnished the following average 

 results : 



filrenyth of ~.' hy 2 pieces ol ].': per cent moisture. 



ICiml of 1e.«t. 



Tree No. 001. Tree ITo. 802. Tree No. 603. 



I 



Pounds per ' Pounds per Pounds per 



#</. III. iq. in. »q. in. 



f.'omprission enilwi.ii- 0,710 0,800 6,340 



I'.cnililiv' to rilalive elastie limit 7.960 7,970 7,800 



ISoniliiit- to rupture 9,300 (i, 030 i 9.340 



Modulus of clastiiitv (1.000 pnuiidsi 1.306 1,291 I 1,285 



It is ai)paient from the abo\-e that the jierfeet i|uarter-sawed material conlirmed the other 

 test results in showing the great similarity of tiie wood of these three trees. It also shows, how- 

 ever, that the effect of defects in an iinselected lot reduces the strength values markedly in this 

 species. 



Arranging the results acconiing to the position of the test pieces in the log, it is found that in 

 compression endwise the strength was: Center pieces, 5,520 pounds, or 78 per cent; intermediate, 

 7,000 pounds, or 100 per cent; outside pieces, C,O.SO jiounds, or !)•"> per cent; showing that the 

 heart pieces, as has been found in other conifers, are always the weakest, thus verifying the results 

 of the general series. The slight decrease from the intermediate to the outside pieces is in keeping 

 with the smaller weight of the latter and need not be ascribed to the fact that these jiieces con- 

 tained small jiroportioiis of sai)wood. As might be e.\i>ected, the uniformity of results in this 

 l)ropeily selected and i)repared material M-as greater than in the ordinary series. Of 58 tests, all 

 tell within -'> per cent of the average strength and 7(i per cent within 10 per cent of the average. 



In connection with a general study into the maximum uniformity of wood, three scantlings of 

 AVhite IMiie. with an average s])ecilic gravity of aljout 0..'!l and an average com])ressive strength 

 at S per cent moisture of 4,1)00 pounds, were examined, two being tested air dry (8 per cent) and 



