198 Mr Wimperis, Some Experiments upon Beams 



A formula of this type will be found to fit experimental results 

 more nearly than the ordinary Eulerian equation, and as an example 

 of its use the fourth and eighth columns of the table show values 

 of P derived from the formula 



p = ToV^ 2 ' ( Formula ' 2> ) 



Table II. 







l-H 



IN 







rH 



<N 



Length of 

 Strut in 

 inches 



Maximum 



Load in lbs. 



(observed) 



Maximum 

 Load in lbs. 

 from Formula 



Maximum 

 Load in lbs. 

 from Formula 



Length of 

 Strut in 

 inches 



Maximum 



Load in lbs. 



(observed) 



Maximum 



Load in lbs. 



from Formula 



Maximum 



Load in lbs. 



from Formula 



71-9 



11-3 



12-3 



11-6 



110 



536 



523 



458 



60-0 



16-5 



17-6 



16-6 



10-0 



645 



634 



545 



48-0 



26 



27-5 



26-0 



9-0 



673 



784 



660 



42-0 



33 



36-1 



33-8 



8-0 



941 



1,010 



811 



36-0 



46 



49-0 



46-0 



7-0 



1,207 



1,290 



1,020 



30-0 



67 



70-4 



66-0 



6-0 



1,450 



1,760 



1,310 



24-0 



105 



110 



103 



5-0 



1,642 



2,540 



1,720 



18-0 



180 



196 



180 



4-0 



2,390 



3,960 



2,310 



14-9 



263 



285 



258 



3-0 



2,770 



7,050 



3,160 



12-0 



401 



440 



390 



2-0 



2,925 



15,900 



4,280 



This fits as well perhaps as any expression of this type would do. 

 Even a modified formula of this form only gives results over a 

 limited range owing again to the complexity of the phenomena ; 

 one phenomenon for 3-inch and 2-inch struts, being the bursting 

 of the conical ends under the great pressure applied. 



The table here given ranges from a strut length of 6 feet to 

 one of 2 inches, and naturally such a variation in length tests any 

 formula very severely. If the series had been split up into several 



