A light exists in spring

A light exists in spring
Not present on the year
At any other period.
When March is scarcely here

A color stands abroad
On solitary hills
That science cannot overtake,
But human nature feels.

It waits upon the lawn;
It shows the furthest tree
Upon the furthest slope we know;
It almost speaks to me.

Then, as horizons step,
Or noons report away,
Without the formula of sound,
It passes, and we stay:

A quality of loss
Affecting our content,
As trade had suddenly encroached
Upon a sacrament.