Beam XLV was tested March lltli, 1893, with the annular rings 

 as in Fig. 90. 



I I I 



8 SO +4 + 00. 4-86 SO 



The load upon the be.-iin was gradually increased until it amounted 

 to 24,850 Ibs., when it failed by the tearing apart of the fibres on the 

 tension side. 



The maximum skin stress corresponding to this load is 3(181 Ibs. 

 per square inch. 



The co-efficient of elasticity, as determined from ;in increment in the 

 deflection of .81-in. between the loads of 2500 and 12,000 Ibs., is 

 956,540 Ibs. 



Table P shows the several readings. 



Beams XLVI and XLVII are the two ends of Beam XLV, tested 

 on March llth, 1893, the central portion containing the fracture having 

 been cut out. 



Beam XLVI was tested March 30th, 1893, with the annular rings as 

 in Fig. 91. 



The load upon the beam was gradually increased until it amounted to 

 44,400 Ibs., when it failed by the tearing apart of the fibres on the ten- 

 sion side. 



The maximum skin stress corresponding to this load is 2740 Ibs. 

 per square inch. 



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

 deflection of. 23-in. between the loads of 10,000 and 25,000 Ibs., is 

 536,770 Ibs. 



Table P shows the several readings. 



Beam XLVII was tested March 30th, 1893, witli the annular rings 

 as in Fig. 92. 



The load upon the beam was gradually increased until it aiuounte \ 

 to 48,650 Ibs., wli2n it failed by the tearing apart of the fibres on the 

 tension side. 



The maximum skin stress corresponding to this load is 3003 Ibs 

 per square inch. 



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

 deflection of .2-in. between the loads 10,000 and 25,000 Ibs., is 617,283 

 Ibs. 



Table P shows the several readings. 



Beams XLVIII to L were sent to the laboratory by Mr. P. A. 

 Peterson. These beams were purchased from the Pembroke Lumber 

 Company, and are supposed to have been similar in quality to the 

 timber used on the Pembroke section of the Canadian Pacific Railway. 



Beam XLVIII was tested March 1st, 1894, with the annular rings 

 as in Fig. 93. The darkened portion, Fig. 96, represents sapwood. 



The load upon the beam was gradually increased until it amounted 

 to 38,100 Ibs., when the beam failed by the crippling of the material 

 at the support on the compression side, Fig. 94. The load was still 



28 



