Classic Poem

‘Upon its southern point there grows an elm—
It's braved the floods and storms for many a year—
Which pilots recognize with starboard helm
When up the stream their freighted barks they steer.
The midnight moon will shine upon it clear;
Twelve paces from its base, by measure made,
The shadow of its forks will plain appear;
Upon that spot descend with bar and spade,
For bloody Robert's wealth is underneath you laid.