Why does Kipling repeat the pattern "Presently the ...

In the beginning of years, when the world was so new and all, and the Animals were just beginning to work for Man, there was a Camel, and he lived in the middle of a Howling Desert because he did not want to work; and besides, he was a Howler himself. So he ate sticks and thorns and tamarisks and milkweed and prickles, most ‘scruciating idle; and when anybody spoke to him he said ‘Humph!’ Just ‘Humph!’ and no more.

Presently the Horse came to him on Monday morning, with a saddle on his back and a bit in his mouth, and said, ‘Camel, O Camel, come out and trot like the rest of us.’

‘Humph!’ said the Camel; and the Horse went away and told the Man.

Presently the Dog came to him, with a stick in his mouth, and said, ‘Camel, O Camel, come and fetch and carry like the rest of us.’

‘Humph!’ said the Camel; and the Dog went away and told the Man.

Presently the Ox came to him, with the yoke on his neck and said, ‘Camel, O Camel, come and plough like the rest of us.’

‘Humph!’ said the Camel; and the Ox went away and told the Man.

At the end of the day the Man called the Horse and the Dog and the Ox together, and said, ‘Three, O Three, I’m very sorry for you (with the world so new-and-all); but that Humph-thing in the Desert can’t work, or he would have been here by now, so I am going to leave him alone, and you must work double-time to make up for it.’