"Here the Madonna appears as the Queen of the Heavenly host, in a brilliant glory of countless angel heads, standing on the clouds, with the Eternal Son in her arms; St. Sixtus and St. Barbara kneel at the sides. Both of them seem to connect the picture with the real spectators. A curtain, drawn back, encloses the picture on each side: underneath is a light parapet, on which two beautiful boy-angels lean. The Madonna is the one of the most wonderful creations of Raphael's pencil: she is at once the exalted and blessed woman of whom the Saviour was born, and the tender earthly Virgin, whose pure and humble nature was esteemed worthy of so great a destiny. . . . The Child, enthroned in her arms, rests naturally, but not listlessly, and looks down upon the world with a serious expression. . . . The eye is with difficulty disenchanted from the deep impressions produced by these two figures; so as to rest upon the grandeur and dignity of the Pope, the lowly devotion of St. Barbara, and the cheerful innocence of the two angel children. This is a rare example of Raphael's later time, executed entirely by his own hand. No design, no study of the subject for the guidance of a scholar, no old engraving, after such a study, has ever come to light. . . ." [P. 11.]
Catalogue of Paintings, Engravings, &c., &c. at the Picture Gallery of the Artists' Association and of the Maryland Historical Society. Baltimore: Printed by John D. Toy, corner of Market and St. Paul Streets. 1856.