1901.] on Enamels. 511 



All these uses of the word enamel are, strictly speaking, incorrect. 

 True enamel consists of glass, melted on to the surface of metals or 

 of pottery by means of intense heat. But in all these cases the 

 substance is the same — it is glass. 



Glass consists of silica united with soda or potash, either simply 

 or with the oxides of various earths, such as lime, magnesia, or 

 alumina ; and the colouring matter is supplied by the addition of 

 small quantities of iron, copper, cobalt, manganese, chromium and 

 other metals. 



The glazes upon china, porcelain, earthenware, bricks, tiles, iron 

 saucepans, and on copper, are all of the same character, simply con- 

 sisting of various sorts of white or coloured glass, and this glaze may 

 be made, by means of heat, to adhere like a varnish upon the surface 

 of any substance, which will not melt when raised to the temperature 

 necessary to fuse the glass. But when ordinary glass, composed of 

 silica and soda or potash, is melted and run on to china, it cracks, 

 or as it is termed in old English phrase, " crazes." A crazed plate is 

 unfit for domestic use, for the hot grease is apt to penetrate through 

 the cracks under the ware, and to produce stains, and make the 

 crockery offensive and insanitary. In order to prevent " crazing," it 

 is necessary to mix some alumina, or clay, or some lime, or magnesia, 

 with the glass. But these substances render the glass so hard to 

 melt, that in order to lower its fusibility some lead or borax must 

 be added. Of these, lead is the best, for it makes the glaze tough, 

 elastic, and to flow freely. Borax makes the glaze more apt to 

 crack, and liable to be affected by moisture. 



The use of lead of course involves the danger of lead-poisoning. 

 In the present state of the pottery trade, it is too much to ask that 

 lead should be totally disused, but it is possible to prevent the work- 

 men from handling it in a raw state, and thus its danger may be very 

 greatly diminished. 



Enamelling was known to the Greeks, probably also to the 

 Egyptians and to the Scandinavians. But it seems first to have 

 been brought to perfection by the Byzantines, and chiefly, though 

 not exclusively, in Christian art. 



In its later forms Greek art reflected the feelings and the 

 degeneracy of a dying world. Those who desire to experience it will 

 find it in literature in the Milesian tales, or the Golden Ass of 

 Apuleius. In sculpture it is reflected in the small tinted statuettes 

 to be found in most museums. The severity of earlier times has 

 given place to a cloying sweetness, which, though charming, is 

 instinctively felt to be wanting in manly vigour. 



With Christianity art took a severer form. The early Christian 

 Church had before her eyes the spectacle of a world which had 

 perished through the immoderate use of art. Weary of the babbling 

 of the schools of rhetoric, men turned to the silence of the cloister. 

 The desert was a necessary protest against the luxury of later Roman 

 times ; celibacy was a reaction against universal sexual profligacy. 



