What is to examine, as the thickness of the metal at the muzzle of a gun; or, in general, to examine the thickness of, as ordnance, in order to ascertain its strength called?

tertiate — (Gun.) To examine, as the thickness of the metal at the muzzle of a gun; or, in general, to examine the thickness of, as ordnance, in order to ascertain its strength. (Webster's 1913.)

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