Simplification

When you see upon the walk
Circles newly made of chalk,
And around them all the day
Little boys in eager play
Rolling marbles, agates fine,
Banded, polished, red as wine,
Marbles crystal as the dew,
Each with rainbows twisted through,
Marbles gay in painted clay,
Flashing, twinkling in your way,
When the walk has blossomed so,
Surely every one must know
None need wonder who has heard
Robin, wren, or Peter-bird;
Sure the sign as song or wing,
          It is spring!