Gnomons

In April, thirteen centuries ago,
Bede cast his cassocked shadow on the ground
Of Jarrow and, proceeding heel-to-toe,
Measured to where a head that could contain
The lore of Christendom had darkly lain,
And thereby, for that place and season, found
That a man's shade, at the third hour from dawn,
Stretches eleven feet upon the lawn.
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