by C. S. Lewis

The mind too has her fossils to record her past,
Cold characters, immobile, of what once was new
And hot with life. Old papers, as we rummage through
Neglected drawers, still show us where the pen, fast, fast,
Ate up the sheets: and wondering, we remember vast
Designs and knowledge gathered, and intent to do
What we able then to have done . . . something drew
A sponge across that slate. The ferly would not last.

Though Will can stretch his viaduct with level thrust
High above shagg’d woods, quaking swamp, and desert dust
Of changing times, yet he must dig for his material
In local quarries of the varying moment—must
Use wattle and daub in countries without stone, and trust
To basest matter the proud arches’ form imperial.