Seel’d his broad eye. The healthful air had here
Free entrance, and the cheerful light of heaven;
But at the end, an opening in the floor
Of rock disclosed a wider vault below,
Which never sun-beam visited, nor breath
Of vivifying morning came to cheer.
No light was there but that which from above
In dim reflection fell, or found its way,
Broken and quivering, through the glassy stream,
Where through the rock it gush’d. That shadowy light