TENSILE STRENGTH OF BOILER PLATE. 



413 



Collecting the results of these experiments, tabulated above, it will be 

 necessary to exhibit them in a more condensed form, so as to facilitate com- 

 parison, and to deduce the laws which regulate the tensile strength of wrought 

 iron. We may then apply the results of these experiments to a much greater 

 variety of plates produced in the different districts of England. It will be 

 borne in mind that the ordinary Staffordshire plates, such as those experi- 

 mented upon (unless they are double-worked), are rather inferior in quality 

 to the Shropshire and Derbyshire plates, and much more so to those manu- 

 factured at the Lowmoor and Bowling Works. Hence the comparison will 

 only hold good between the Staffordshire plates in each case. 



General Summary of Results. 



From the above Table we may deduce the following : — 



* Some steely spots in fracture. 

 X Too high, fracture very uueven, 

 II Too low, tore through eye. 



t Fissure containing scoria. 



§ Did not break at smallest section. 



f Too high, see Table. 



