Chap. II. DON BARTOLOMMEO. 37 justified the choice by covering the empty spaces with frescos, and by the invention of an organ of pasteboard, which yielded the truest and softest of tones. Not con tent with adorning the interior of his home, he found occasion to eke out the poor sustenance of his brother- friars by taking commissions for altar-pieces, and thus showed himself a benefactor of his order. 1 It is not possible to assign dates to these events, nor are there means of ascertaining how della Gatta made the acquaintance of Signorelli and Perugino, though he might have met them at Arezzo, if it be true that they were both assistants to Piero della Francesca. It is enough to state that he did not owe his education in art to either of them. Time has disposed of all his minia tures; though some are ascribed to him of which the au thenticity is a matter of dispute; 2 but panels exist at Arezzo, from which we judge that, previous to visiting Rome, he had acquired a style of his own, in which pa tience and carefulness are distinguishing characteristics. He is said to have begun painting on a large scale during the years which followed the outbreak of the plague at Arezzo (1468) ; 3 and this is correct insofar that we possess two out of three panels representing the invocation of the plague saint, S. Roch, commissioned for religious houses in Arezzo; and that one of them, originally in the Brother hood of mercy and now in the Town hall, bears the date of 1479. It presents to our view the square of the city, on which the tile coloured house of the Brotherhood of mercy is erected. Three grave-diggers at the foot of the door-steps stand on the particoloured marbles of the pave ment. They have just returned from burying some plague- stricken corpses. S. Roch is on the foreground, a thin slender figure in a gentle attitude, looking up bareheaded to heaven and his hands joined in prayer. A long staff 1 Vas. V. 49. 2 The choral books in the Cathe dral of Lucca, and one of old be longing to S. Egidio now at the Magliabecehiana in Florence, have been quoted as containing minia tures assignable to Della Gatta; but no one can certify to their genuine ness (see annot. Vas. V.44—5). 3 Vas. V. 45.