Lines 7-18 Summary

Lines 7-8

And the saw snarled and rattled, snarled and rattled,
As it ran light, or had to bear a load.

• Repetition, repetition, repetition. Why say line one again? Well, first off, what does a saw do? It cuts and cuts repeatedly. We get a sense of the repetitiveness of the task here, sawing wood. Also, it gives the reader a sensory experience. You read those lines and you can hear the saw in your head—over and over again. 
• This repetition between the saw cutting logs and the saw still running between logs changes up the noise. It's running "light" while the boy prepares a new log, and it "bears a load" when the boy is feeding wood through the saw. 
• Notice though, that the boy still hasn't been mentioned. The saw runs light, not the boy. The saw is still the subject here. The machine is taking on man's tasks—usually we think of men and women "bearing loads" literally or figuratively. It's a metaphor for work, and implies that things are being dealt with, produced, and carried. But here, it's the machine taking on the metaphor as well as the work itself.

Line 9

And nothing happened: day was all but done.

• Wait just a darn minute. Isn't the point of any poem that something happens worth mentioning? The idea here is not to turn you off, but to make you see that nothing out of the ordinary has happened yet. This is a normal day on the farm, and it was about to end, when... the action of the poem happens. 
• Also see here how Frost uses meter (iambic) to have this line sing. It's concise, simple, and the very cadence of the line reinforces its message. In the second half of the sentence, notice the alliteration of the D words. This creates a tone of seriousness, finality, and purpose.

Lines 10-12

Call it a day, I wish they might have said
To please the boy by giving him the half hour
That a boy counts so much when saved from work.

• The speaker pops into the first person for a moment here to lament what happens later in the poem. Although day is almost gone, the boy still had half an hour of work left. If only he had been given the day off, then the unthinkable might not have occurred. 
• Notice how Frost appropriates a colloquialism—"call it a day"—here to great effect. The speaker uses the vernacular of simple country folk, and we understand that he (we assume it's a he) shares much in common with the people whose lives he's describing in the poem. 
• Also, of supreme importance in these lines: notice how we have different perspectives on work. For a man, working half an hour doesn't make as much difference, but to a boy doing a man's work, half an hour lost or gained is a huge deal. These lines are a reminder that the poem is interested in different ideas of work and masculinity. 
• In this hypothetical tangent, the boy is still "saved" from work, as opposed to tragedy. This can be read in terms of saving time, and also being saved from doing more work by a merciful relative.

Lines 13-14

His sister stood beside him in her apron
To tell them "Supper."

• Again, we get these simple, picturesque country images—a domestic female summoning the men in for supper. Can't fight it folks, this is the 1910s—clichés abound. 
• Notice how Frost uses these images to create a scene of normalcy and calm. Just an ordinary day, and an ordinary supper call.

Lines 14-18 

At the word, the saw,
As if to prove saws know what supper meant,
Leaped out at the boy's hand, or seemed to leap—
He must have given the hand. However it was,
Neither refused the meeting. But the hand!

• So what happens in these lines? Frost melds the imagery of the boy hitting his hand on the saw, and the imagery of the saw hitting the boy's hand. In a nutshell, the boy cuts his hand. But Frost refuses to give complete responsibility for the accident to the boy, and his description also seems to better match the strangeness and horror of the scene (with more personification of the saw). 
• We can't quite see what happened—the saw "leaped," or "seemed to leap"—and the logical conclusion follows, that the boy must have "given the hand" to the saw. This line is particularly striking because a saw, like all tools, is an extension of a human.
• We create tools to help us work easily, and we in effect sign over the difficult parts of work to these tools. In this exchange, though, the boy is giving his hand to the saw, and it's as if the machine is the entity in charge, not the human. 
• So what's the deal with this "proving" business? The real person with something to prove here is the boy (not the saw), because he is doing a man's work. The saw is treated almost as though it were a true character with a personality. The boy is excited for supper, but this blending of personalities and motives raises questions of work and production. When we use tools, do we become instruments ourselves? Is it the saw's fault or the boy's?
• What Frost is describing happened in the space of a millisecond, but it's afforded these four full lines because the speaker wants to sort through the intensity of the scene. 
• And what does "neither refused the meeting" mean? Again, the speaker is trying to describe something that happened in the blink of an eye. It was fast, horrific, and he's working to piece it together. So, on reflection, neither the boy nor the saw refused to meet. It seems that both share in the guilt for what happens next.