The flats were all his that morning.

Only the cart and its driver were in sight and they were half a mile off.

He looked at his watch, sighed, and reluctantly started to walk toward the town; he mustn't keep Mrs.Coffin's breakfast waiting TOO long.
The first channel he came to was considerably deeper than when he forded it on the way out.

He noticed this, but only vaguely.

The next, however, was so deep that the water splashed in at the top of one of his boots.
He did notice that, because though he was not wearing his best clothes, he was not anxious to wet his "other ones." The extent of his wardrobe was in keeping with the size of his salary.
And the third channel was so wide and deep that he saw at once it could not be forded, unless he was willing to plunge above his waist.