Note 265 — Chapter XVIII · (XXXII.)

The ‘occhi’ of Vasari correspond to the old-fashioned ‘bull’s-eyes’ which are still to be seen surviving in cottage windows. The ‘bull’s eye’ pane was the middle part of a sheet of so-called ‘crown’ glass where was attached the iron rod or tube with which the mass of molten glass was extracted from the furnace, before, by rotation of the rod, it was spread out into the form of a sheet. When the rod was ultimately detached a knob remained, and this part of the sheet was used for glazing as a cheap ‘waste product.’ In connection with the modern revival in domestic architecture, for which Mr Norman Shaw deserves a good deal of the credit, these rough panes have come again into fashion, and manufacturers make them specially and supply them at the price of an artistic luxury! In Vasari’s time they were evidently quite common, and we find numerous specimens represented in the pictures of the fifteenth and sixteenth centuries. The bedroom of S. Ursula in Carpaccio’s picture at Venice; the cell of S. Jerome in Dürer’s engraving; the room in which van Eyck paints Arnolfini and his wife, those in which Jost Amman’s ‘Handworkers’ are busy, etc., etc., have casements glazed in this fashion, the knob, called in English ‘bullion,’ in French ‘boudine,’ in German ‘Butzen,’ being distinctly represented as in relief.