4^ THE STRENGTH 



Now from the principle of the lever, (see 

 problem further on) the strength of half of a 

 beam so broken, is to the strength of the whole 

 beam, as 3 to 2. 



Hence, as the whole beam broke with 

 19441 lbs. the half should not have broke with 

 less than 29161 lbs. We have no data to prove 

 whether this would or would not have borne 

 that weight, 26497 lbs. only having been laid 

 on it; it is however probable that it would have 

 borne it or a greater weight. 



Another half of a beam of nearly the same 

 dimensions, and which must either have belonged 

 to that in experiment 15 or 16, broke as before 

 in its middle, with 22255 lbs. the breadth of 

 the bottom rib, at the place of fracture, being 

 4.6 inches. 



Now 2:3:: 16905 (expt. 15) : 25357 lbs. 

 „ 2:3:: 14336 (expt. 16) : 21504 lbs. 



Hence, the strength of the end of the beam 

 was a little in defect or excess, according as it 

 belonged to the former or the latter of these 

 experiments. 



JflG ^^^' 



•10 The beams in the preceding four experiments, 

 commencing with experiment 14, were cast 



