•f^i] 



OF IRON BEAMS. 4^1 



XX. EXPERIMENT. 



Beam from the same model as that in the last 



experiftient. 



Distance between supports as before. 



Dimensions of section in inches, (see fig. last expt.) 



Area of top rib = 2.3 x .28 = .64, 

 Area of bottom rib = 6.63 x .65 = 4.31. 

 Thickness of^ 

 • vertical part,) ~ •^^^• 

 Area of section 6.5, or 6i inches. 

 Weight of beam = 74| lbs. 



^n\t^ , DeaectioM Ra.n,ed (o 



•° *'»•• 1° P*rts of inch. (weights taken off.) 



9328 .22 - - . . - - 



11397 24 - •in.fu^ii - Q 



12777 .25 -. 



14345 ------ .26 .03 



15913 ---.-. .30 .04 



,d/ 17481 - .34 



18265 -;-r-- -36 



19049 - .^-- - .38 



20617 .43 



22185 .47 



22969 .48 



50 



It broke in the middle of the beam by tension, 

 with 23249 lbs. or 10 tons 8 cwt. nearly. 



This is considerably less than what the former 

 beam bore, though Its bottom rib, in which 



3 p 



