Analysis of The lonesome for they know not What

The lonesome for they know not What—
The Eastern Exiles—be—
Who strayed beyond the Amber line
Some madder Holiday—

And ever since—the purple Moat
They strive to climb—in vain—
As Birds—that tumble from the clouds
Do fumble at the strain—

The Blessed Ether—taught them—
Some Transatlantic Morn—
When Heaven—was too common—to miss—
Too sure—to dote upon!