It may be said generally of the Saracenic enamelled glass as of the unadorned glass of the Byzantines that preceded it, that the lamp in one shape or another is the master form—no longer the wine-cup, as among the Romans. It would be an interesting study, were the thing possible, to trace the steps by which the later arrangement of an outer lantern of glass grew out of the simpler Byzantine or Sassanian prototype. But it must be remembered that these gorgeous mosque lamps or lanterns are quite a specialised form; they are only found, as far as we know, in Egypt and Syria, and they belong essentially to the fourteenth and fifteenth centuries. The typical Oriental glass lamp is of quite a different type—a little cup in the shape of a truncated cone, from four to six inches in height. This is a form that is generally in use in the East at the present day. Such a vessel constitutes the essential part both of the street lanterns (the conical cup in this case passes through an aperture in the base) and of the coronas of lights by which the larger rooms are illuminated. In the latter case the cups pass through apertures in a ring or disc of wood or metal, which is itself suspended, often from an ostrich egg, in the way already described. The little vessels are filled halfway up with water, upon which the oil floats; the wick passes up through a tube which is fixed at the bottom in various ways. I have before me a cup of this description brought from an old house in Cairo; it is of very thin, tough, greenish glass; the ‘kick’ at the bottom is pushed deeply in and is open at the apex. This opening has been sealed up with some hard pitchy substance, into which the little glass tube (of later date apparently) that carries the wick has been fixed. In another type of these cup or beaker lamps the base ends in a blunt point which is prolonged by one or more knops, so as to resemble the stem of a wine-glass without the foot.[113] This is the form that, as I have already mentioned, is so often represented, suspended from the roof in the altar-pieces of the Venetian painters. Such lamps are generally elaborately mounted in metal. But the other form, the truncated cone (the ‘spear-butt’ of Paul the Silentiary), was in use in Italy at an earlier date. In the chapel of the Arena at Padua is a careful wall-painting of an elaborate compound corona or lantern built up with hoops of metal to resemble a large bird-cage. The little lamps of plain glass fitted into this framework are of two shapes; one resembles the truncated-cone cup just described, while the other may be compared to a mosque lamp with the foot removed and the body prolonged to a point. I do not know if this painting is contemporary with the famous frescoes of Giotto that cover the adjacent walls, but to judge from the Gothic framework that surrounds it, it cannot well be later than the fourteenth century.