It may be well to point out that the easel used for painting glass upon is very different to the one in use by artists when painting on canvas, as it consists of two rectangular wooden frames the front one of which sustains the easel glass, upon which the various fragments of glass forming the subject in hand are fastened, by means of a kind of cement made of wax and resin. The frame immediately behind is covered with white tissue paper, a material that not only diffuses the light equally all over the subject which is being painted, but renders the otherwise bright light soft to the artist’s eyes, and prevents the glare of the various pieces of coloured glass from making them ache, as they would do if a naked light were used. Thus, in painting a subject on canvas, the light is thrown upon the front of the easel, but in painting a figure for a church window the light is behind it, and passes through it to show up the transparent colours. I sipped my coffee and admired the monk, especially his eyes, which appeared dark and lustrous and full of life, although his body was of the lay-figure order, and his hands as absurdly grotesque in pose as those of a Chinese mandarin on a tea-tray. Then I turned my attention to the figure of St. Agnes upon my easel and painted away again in a most diligent and vigorous manner. Eleven o’clock came, and I began to grow sleepy and to give an involuntary yawn now and again, but I had resolved to work till midnight, and work I would. Half-past, and I was becoming still more drowsy, and for some reason a certain nervousness seemed to come over me--mental strain and long hours I suppose; but presently I heard a sound as of glass lightly jarring against some metallic or hard substance. I glanced round and tapped my mahl-stick upon the floor, but no mouse scurried away responsive to my sh--h--h! so I resumed work. A little time elapsed, and again I heard the same rattle of glass; very quiet, but quite distinct; it was a sharp, bright, but subdued noise, familiar to my ear as the noise made by glass when touching another hard substance. Again I glanced round: all was silent. Only it seemed to me that the glass monk solemnly returned my enquiring look with a gaze such as that with which the Ancient Mariner fixed the wedding guest. Work again--then another rattle, louder than before. This time I jumped up from my seat, opened the door, thinking some one must be outside, but nothing was to be seen. I looked again at my companion, Friar Aylmer, and this time, to my astonishment, his eyes seemed to move--to blink, in fact (for probably, as a religious man, he never learned the art of winking). I approached, but the eyes were again fixed, fixed full upon me, whichever way I turned. I simply laughed at myself: of course I conjectured that the flickering gaslights in the adjoining room were playing an optical prank upon me.