In his cell of white washed walls

Altis kept a diary

The movement of the sun

And of the stars was all recorded

With the upmost care

Occasionally the guards would invite him

To warm himself in front of the great fire

It was here he took the opportunity

To note the movement of the flames

And of the cooks in the nearby kitchen

He recorded his mathematics on the daub wall

And revised his calculations often

On the occasion of his birthday

He was invited to the Captains House

And was given the gift of a rug

Which was unwoven in front of him

To aid his work

In later life Altis was given permission

To sit in the sun

On the castle walls

And count the lichens

As he admitted their simplicity