VOL. I., PLATE 25. [Illustration: THE LAST SUPPER Central Panel of a Triptych BASEL GALLERY ] [Sidenote: THE VISIT TO LOMBARDY] Still stronger evidence of this journey to Lombardy is to be found in Holbein’s numerous designs for painted glass,[173] which he produced during the next six or seven years, designs which, in most cases, are filled round the borders and in the backgrounds with rich and elaborate architecture based upon Renaissance models. It is difficult to understand how he could have produced so much work of this nature, so filled with the beauty and dignity of the style upon which it was founded, had he not had at least some personal acquaintance with the original examples upon the far side of the Alps, which these drawings of his so often suggest. A close comparison of certain of these studies with the architectural details of some of the splendid Renaissance buildings which he must have seen if this journey across the plains of Lombardy did in reality take place, makes it almost certain, although there are no documentary proofs, that he made drawings and sketches of some of the principal edifices of Milan, the façade and interior of the Certosa of Pavia, the monumental tombs of architectural design which are to be met with throughout Northern Italy, and such cathedral churches as those of Como and Lugano;[174] and that he must have studied also the use made by the Italian painters of similar architectural features in the backgrounds of their frescoes and paintings. It is difficult to believe that his intimate knowledge of the true principles of that style were gained merely by the study of a few engravings or isolated pictures. Here and there, too, in those glass designs in which the background is a landscape, there is more than one Alpine scene. In the one with the figure of a Pope or Bishop, in the Basel Gallery (No. 334),[175] there is a view of the old Devil’s Bridge on the Andermatt route, and the same bridge is to be seen in the “Table of Cebes” woodcut. There is a view of the Rigi in the background of the woodcut of “Jacob’s Ladder” in Thomas Wolff’s edition of the Pentateuch, 1523, and, again, a representation of Lucerne in the woodcut of the “New Jerusalem,” in the same publisher’s edition of the New Testament, 1523 (Pl. 70 (3)).[176]