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IV. Method Adopted 



1. Test of Transverse Strength. 



The span of beam was taken as 98 inches and it was supported at two 

 ends; load was charged at the middle; deflection of the beam was duly 

 read by the gradual increase of loading in weight till the beam finally 

 breaks. 



The cross-head and the supports in the two ends of the beam are 

 obtuse wedge shaped so that they will not cut into the beam, but with a 

 few species, the beams were damaged to some extent. Further, to rectify 

 the defect arising in the determination of deflection, the distance from 

 the base of the machine to the mark made on the neutral plane of the 

 beam at one end just above the support as well as the distance from the 

 same base to the mark at the middle of the beam on the same plane 

 where the load falls were duly read, and the difference of the two distances 

 so obtained was taken as the true deflection. The increase of load differs 

 according to the size of the beam subject to the test. With small beams 

 every increase of 0.2 tons, with large beams 0.5 tons was read to deter- 

 mine the deflection. The work was effected both for small and large 

 beams without pause until complete rupture set in. 



The results of the tests with maximum, minimum and mean will be 

 learnt from the subjoined Table I-IV. 



2. Strength of Wood and its Modulus of Elasiicity Tested. 

 Results of the bending tests of a few typical beams. 



