----Try Leopardstown! Said a voice from the bench behind.

Stephen glanced up quickly but Moynihan's snoutish face, outlined on the grey light, was impassive. A formula was given out. Amid the rustling of the notebooks Stephen turned back again and said:

----Give me some paper for God's sake.

Are you as bad as that? asked Moynihan with a broad grin.

He tore a sheet from his scribbler and passed it down, whispering:

----In case of necessity any layman or woman can do it.

The formula which he wrote obediently on the sheet of paper, the coiling and uncoiling calculations of the professor, the spectrelike symbols of force and velocity fascinated and jaded Stephen's mind. He had heard some say that the old professor was an atheist freemason. O the grey dull day! It seemed a limbo of painless patient consciousness through which souls of mathematicians might wander, projecting long slender fabrics from plane to plane of ever rarer and paler twilight, radiating swift eddies to the last verges of a universe ever vaster, farther and more impalpable.

----So we must distinguish between elliptical and ellipsoidal. Perhaps some of you gentlemen may be familiar with the works of Mr W. S. Gilbert. In one of his songs he speaks of the billiard sharp who is condemned to play:

On a cloth untrue
With a twisted cue
And elliptical billiard balls.


----He means a ball having the form of the ellipsoid of the principal axes of which I spoke a moment ago.

Moynihan leaned down towards Stephen's ear and murmured: