But glad with him, I worked as with his aid, And weary, sought at noon with him the shade;
And dreaming, as it were, held brotherly speech With one whose thought I had not hoped to reach.
'Men work together,' I told him from the heart, 'Whether they work together or apart.'
The speaker goes on turning over the grass, still feeling good about his connection to the absent mower.
Finally, around noon, he knocks off for lunch. He goes to take his break in the shade (naturally) and the mower hangs out with him—woah, hold up another second.
It seems like the speaker is, again, imagining the mower. He calls it "dreaming" (39).
In this dream, he talks to the mower ("held brotherly speech") (41).
At first he couldn't believe that this was possible—remember back in line 8? But now the speaker's totally changed his tune.
All that stuff about being totally alone in the world? J-K'ing, y'all—the speaker has changed his tune. He really means it, too. He's speaking "from the heart," to the (imaginary) mower (41).
And what he's saying is that "men" (meaning men and women) work together, whether they're standing right next to each other or in totally different spaces.
As the speaker notices the mower's work, he realizes that he's connected to the mower in that moment.
Think about it like this: the computer or phone you're reading this on? Somebody, somewhere made that. In the same way as speaker and mower, you are connected to that person. And if you follow that logic, then we may all be connected to each other, everywhere, all over the world.
At least, we're much less alone than we might think.
In fact, by reading these very words you are connected to us—and we're connected to you. Isn't that nice?