TENSILE STRENGTH OP BOILER PLATE. 



Table XII Strain applied in the direction of the fibre. 



Boiler plate ; sectional area =2*0 X •32=*64' sq. inch. 



411 



In this experiment the plate gave way at the shackle, the bolt which held 

 the plate tearing through the eye, and forcing away a four-sided piece as the 

 plate was about to yield to the weight on the lever. We may therefore 

 safely assume 31,980 or 32,000 lbs. as the ultimate strength or breaking 

 weight of the plate. 



Table XIII. — Strain applied across the fibre. 

 Boiler plate ; sectional area =2"0 x*34'=*68 sq. inch. 



The mean result of experiments XII. and XIII. is 46,014 lbs., or about 

 20J tons per square inch, evidently showing that the iron is in no degree 

 injured by a temperature ranging from zero up to 340°, and this temperature 

 may probably be increased as high as 500° or 600° without seriously 

 impairing the strength, as may be seen in the following Table at nearly 400°. 



Table XIV. — Strain applied in the direction of the fibre. 

 Boiler plate; sectional area =2*02 x '33 ='6666 sq. inch. 



The only difference between this and the last two experiments is the 

 increased elongation, which in the latter was 1'25, and in the former 'IS 



