TIMBER PHYSICS STRENGTH AND WEIGHT. 



367 



Eeswltb of tests in hending f at relative elastic limit, 

 [Pounds per square inch.] 



No 



5 

 6 



7 

 8 

 9 

 10 

 11 

 12 

 13 

 14 

 15 

 16 

 17 

 18 

 19 

 20 



22 

 23 

 24 

 25 

 26 

 27 

 28 

 29 

 30 

 31 

 32 



Species. 



Reduced to 15 per cent moisture. 



Longleaf pine. 

 Cuban pine... 

 Shortleaf pine 

 Loblolly pine . 



Reduced to 12 per cent moisture. 



White pine 



Red pine 



Spruce pine 



Bald cypress 



White cedar 



Douglas spruce a ... 



White oak 



Overcup oak 



Post oak 



Cow oak 



Red oak 



Texan oaK * 



Yellow oak 



Water oak 



Willow oak 



Spanish oak 



Soagbark hickory . 

 Mockernut hickory 



Water hickory 



Bitternut hickory . 

 Nutmeg hickory . . . 



Pecan hickory 



Pignut hickory 



White elm 



Cedar elm „ 



White ash 



Green ash 



Sweet gum 









Average 



Average 







Highest 



Lowest 



of high- 



of lowest 



Average 

 of all 



of tertt.a. 



single 



single 



est 10 per 



10 per 





test. 



test. 



cent ol 



tests. 



cent of 

 tests. 



tests. 



1,160 



13, 500 



2,400 



11, 100 



5,400 



8,500 



390 



12, 900 



2,200 



11, 500 



5,600 



9,500 



330 



1J.900 



2,900 



9,700 



4,800 



7,200 



050 



12, 700 



3,100 



10, 800 



5,400 



8, 200 



130 



10, 000 



4,100 



8,200 



4,500 



6, 400 



95 



11, 300 



3,100 



10, 300 



4,500 



7,700 



170 



13, 700 



3,000 



11, 200 



5,000 



8,400 



655 



12, 000 



2,200 



9,900 



4,200 



6,600 



87 



8,200 



3,400 



7,390 



4,000 



5,800 



41 



13, 700 



2,800 



9,600 



3,400 



6,400 



218 



15, 700 



4,400 



14, 100 



6,100 



9,600 



216 



11, 600 



4, 000 



9,500 



5,400 



7,500 



49 



10,600 



5,100 



9,600 



6,000 



8,400 



256 



14, 200 



3,400 



11, 600 



5,000 



7,600 



57 



14, 500 



5,100 



13, 600 



5,600 



9,200 



117 



12, 000 



5,900 



11, 400 



7,800 



9,400 



40 



11, 800 



4,900 



11, 100 



5,100 



8,100 



31 



11, 800 



4,500 



11, 400 



5,500 



8,800 r 



153 



13, 100 



2,700 



10, 000 



4,300 



7,400 



257 



13, 500 



5,100 



11, 600 



6,600 



8,600 



187 



16, 100 



5,400 



14, 200 



7,700 



11,200 



75 



15, 400 



4,300 



14, 600 



7,800 



11, 700 



14 



11, 900 



4,100 



11, 800 



4,800 



9,800 



25 



14, 300 



7,500 



14, 000 



7,600 



11, 100 



72 



12, 200 



4,200 



11, 200 



6,400 



9,300 



37 



15, 000 



5,800 



14, 400 



7,900 



11, 500 



30 



17, 500 



7,400 



16 400 



8,300 



12, 600 



18 



9,700 



5,300 



9,600 



5,400 



7,300 



44 



10, 700 



4,700 



10, 100 



5,800 



8,000 



87 



11, 500 



3,600 



10, 400 



5,200 



7,900 



10 



13, 200 



3,200 



13, 200 



3,200 



8,900 



118 



11, 000 



3,500 



10, 100 



5,100 



7,800 



Proportion 

 oi tests 



within 10 

 per cent of 



average. 



Per cent. 

 43 

 42 

 48 

 46 



58 

 38 



51 

 25 

 44 

 32 

 37 

 47 

 34 

 50 

 15 

 62 

 35 

 40 



50 

 39 

 21 

 44 

 46 

 65 

 40 

 33 

 57 

 43 

 40 

 46 



Proportion 

 of tests 



within 25 

 per cent of 



average 



Per cent, 

 81 

 83 

 81 

 85 



85 

 73 

 82 

 66 

 86 

 56 

 73 

 91 

 76 

 95 

 49 

 94 

 75 

 84 

 81 

 B0 

 89 

 83 

 86 

 84 

 93 

 89 

 83 

 71 

 91 

 83 

 70 

 82 



Modulus of 

 elasticity 



(average of 

 all tests). 



1, 890, 000 

 2, 300, 000 

 1, 600, 000 

 1, 950, 000 



1, 390, 000 

 1,620,000 

 1, 640, 000 

 1, 290, 000 

 910, 000 

 1, 680, 000 

 2, 090, 000 



1, 620, 000 



2, 030, 000 

 1, 610, 000 



1, 970, 000 

 1, 860, 000 

 1, 740, 000 



2, 000, 000 

 1, 750, 000 



1, 930, 000 



2, 390, 000 

 2, 320, 000 

 2, 080, 000 

 2, 280, 000 

 1, 940, 000 

 2, 530, 900 

 2, 730, 000 

 1, 540, 000 

 1, 700, 000 

 1,640,000 

 2, 050, 000 

 1, 700, 000 



a Actual tests on " dry " material not reduced for moisture. 



/£p0O 



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F-t 



CD 

 ft 

 1X3 



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53 

 O 

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3000 



£ 8000 



17000 



6000 



£000 



35 40 45 



Weight per cubic foot in pounds. 



Jig. 95 — Relation of strength in compression endwise to weight of material. The figure at each point indicates the species 



thereby represented. 



