552 
THE DEVELOPMENT OF ARMOUE, 
u.s. accept. The makers of armour-piercing projectiles naturally are left free to 
of^rmour! f°^ ow an y course of manufacture they think gives the best results, 
piercing but the Government stipulates for full information in chemical analysis 
projectiles. an d as to physical tests, although exceptions may be made in the 
Fig.^ 27 . 
