PHYSICS AND THE INTERNAL COMBUSTION ENGINE 29

IIIIIIII !IIIIIII IIIIIIII

lull-Ill Inn-Ill- IIIIIIII III-lull.-

IIIIIIEEEI IIIIIIIIII

0-1 0-2 0-3 0-4 0.5 0-6 0-7 0-8 0-9 DEPTHOF‘ CASE‘ IN MM.

S

O

s: O

I. I! II II II .-

8‘68

5mm: SCLERESCOPE HARDNESS NUMBERS. L9

Fig. 22.

Curve shewing hardness of Nitralloy Steel, oil treated and reheated to give 64 tons tensile. Nitrated for 90 hours.