[Sir Robert Stawell Ball, Professor of Astronomy at Cambridge and Royal Astronomer of Ireland.] Autograph Signature ('Robert S Ball') cut from letter.

Sir Robert Stawell Ball (1840-1913), Irish astronomer who proposed the screw theory, Professor of Astronomy at Cambridge, Royal Astronomer of Ireland, Andrews Professor of Astronomy, Dublin
Publication details: 
Without place or date. [With letterhead of the Observatory, Cambridge.]
SKU: 21295

The signature ('Robert S Ball') is on a 3.5 x 11 cm slip of paper, laid down on a piece of light-grey paper cut from an album, with the letterhead 'OBSERVATORY, | CAMBRIDGE' on a second slip laid down on the same piece. In good condition, lightly-aged.