Our narrator has a bit of the devil in him. Take the fact that the main character—the main character whose primary characteristic is that she takes a lover—is named "Constance." As in, "faithful." As in, "not going to cheat." Way to rub our noses in it, D.H.
Or take what he says about Clifford's recovery: "he was pronounced a cure, and could return to life again, with the lower half of his body, from the hips down, paralysed for ever" (1.4). This sentence is dripping with irony. The rhythm of the sentence ("cure" and "return to life" juxtaposed with "paralysed for ever") totally undercuts the notion that Clifford has any sort of life to return to.
At the same time, the narrator sometimes works himself up into a frenzy over the beauty of the natural world, like when Connie runs outside one day:
It was really a lovely day, the first dandelions making suns, the first daisies so white. The hazel thicket was a lace-work, of half-open leaves, and the last dusty perpendicular of the catkins. Yellow celandines now were in crowds, flat open, pressed back in urgency, and the yellow glitter of themselves. It was the yellow, the powerful yellow of early summer. And primroses were broad, and full of pale abandon, thick-clustered primroses no longer shy. The lush, dark green of hyacinths was a sea, with buds rising like pale corn, while in the riding the forget-me-nots were fluffing up, and columbines were unfolding their ink-purple ruches, and there were bits of blue bird's eggshell under a bush. Everywhere the bud-knots and the leap of life! (12.1)
The detailed, naturalistic tone—bet you couldn't recognize half of the flowers he mentions—sounds really different from his wry, cynical treatment of humans. Here, he celebrates the natural world with total, almost sexual enthusiasm. Why does the tone shift so dramatically? Maybe Lawrence is commenting on the broken, inconsistent nature of modern life—or maybe he's suggesting what people could be like, if they lived more in harmony with the world.