| Quote #1
Let the boy try along this bayonet-blade
These lines sound like they are spoken by a drill sergeant or an instructor, somebody who wants the "boy" to prepare himself for war. The lines also paint a picture of warfare that is devoid of emotion and life—the steel is "cold" and desires "blood."
| Quote #2
Blue with all malice, like a madman's flash;
The simile comparing the bayonet-blade to a "madman's flash" makes war seem pretty crazy. Moreover, war is so bad it doesn't just kill people, it eats them. Notice that the bayonet is "famishing for flesh." Gross, right?
| Quote #3
Lend him to stroke these blind, blunt bullet-heads
The word "stroke" is kind of erotic. As awkward as it sounds, the speaker wants the "boy" to feel affectionately about his bullets, to treat them like some kind of pet or lover or something. It sounds like he's encouraging the boy to take some kind of perverse pleasure in weapons and warfare, don't you think?