JOURN. R. MICR. SOC. 1918. Pl. I. 



Section No 1. 



Section No. 2. 



Tensile test pieces. 



Fid. 



Fig. 3. 





^ 



\* 



Fig. 6. 

 100 X 



¥ 





^>-.i 





Adiard & Son & West Newman, Ltd., Impr. 



