i \ 1 was tested May 22nd, 1893, with the annular ring* as 

 ii' 1'ii.'. P. Under a load of 15,480 Ibs. it failed by the tearing apart 

 of the fibres mi MM tension face. 



The corresponding maximum skin stress is 7116 Ibs. 



The co-efficient of elasticity as determined by an increase in the 

 iletleetion of ..'!-in. between the loads of 500-lbs. and 8,000-lbs. is 

 1,489, l-'i:. Ibs. 



Table B shows the several readings. 



The weight nf the beam on May llth was 4!) Ibs. (> ozs., or 31.05 

 Ibs. per cubic foot, and the weight on May 22nd was 48 Ibs. 1 oz., or 

 .",11..:; HP*., showing ;i loss of weight while in the laboratory at the rate 

 of .0745-lb. per cubic foot per day. 



Beam VII was tested on May 19th, 1893. In this beam the annu- 

 lar rings r.-in somewhat obliquely as in Fig. 9. Under a load of 

 17.615 Ibs., the beam sheared longitudinally along the plane AB, 

 IML'. 10, the distance between the ends of the portions above and 

 i'l'n av the pline of shear being 3-16ths of an inch. The plane of 

 shear extended to a distance of 46-ins. from the end of the beam. 



. //. 



The maximum skin stress corresponding to this breaking weight of 

 17,iilf> Ibs. is 8712 Ibs. 



The co-efficient of elasticity, as determined by an increase in the 

 deflection of .255-in. between the loads of 500 Ibs. and 8500 Ibs., is 

 2.052,250 Ibs. 



Table B shows the several readings. 



Immediately after the longitudinal shear the jockey weight was run 

 back until it indicated a load of 5090 Ibs. when the lever again floated. 

 The weight was then gradually increased until it amounted to 11,840 

 His., when there was a second longitudinal shear along the plane CD at 

 the other end, Fig. 11. The lap at the plane AB was now increased 

 from 3-16ths in. to 3-10ths in v and the distance between the ends of 

 the portions above and below the plane of shear at the other end of 

 the beam was 3-20ths of an inch. 



Alter this second shear the jockey weight was run back to 6840 Ibs 

 when the lever floated. The load was gradually increased until it 

 amounted to 8990 Ibs., when the beam was fractured by the tearing 

 apart of the fibres on the tension face. 



On May llth, this beam weighed 60 Ibs. 4 ozs., or 40.69 Ibs. per 

 cubic foot, and the weight on May 19th was 59 Ibs. 2 ozs., or 39.92 

 lb. per cubic foot, showing a loss of weight in the laboratory at the 

 rate of .o;t(i25-lb. per cubic foot per day. 



Beam VIII was tested May 22nd, 1893. In this beam the annu- 

 lar rings were oblique! as in Fig. \'l. l.mler a load of 11,700 Ibs. it 

 failed at the support by the tearing apart of the fibres on the tension 

 fade. 



I 



./g. fig./ 3. Fig. 14. 



"' oft*'" rr * T 



fig IS. 



1 



