Adam and Merrils. -2. 



Fig. 4. 



0.5 per cent. Carbon Steel Bar, annealed. Magnification i.i<>f> diams. 

 Red Colour Filter A. 



Fig. 5. 

 Portion of same field. Magnification 4,500 diams. K.i Colour Filter. 



XoTE.— These reproductions have been reduced ])y one-third from the 

 original photographs. 



