2 Words to use with penetration

"My lord, wilt thou permit me to inquire somewhat of thy mercy?" "Thou dost make me insolvent of such a quality when thy keen penetration doth not discover, without inquiry, its existence."

It is a well-settled rule, that the penetration projectiles is proportionate directly to their weight and diameter, and to the square of their velocity.

2 Words to use with  penetration