Ornamented And Stained Glass.*

twelfth-century glass . They occur at the abbey church of St . Denys , and at Poissy , in France , and in the aisles of the choir of Canterbury Cathedral ; but the remains of stained glass of the thirteenth century are abundant . In the south and south-east of Europe the

system of decorating the interiors of buildings Avith mosaic work had been long established ; and the most marked examples are the coarse work at the Cathedral of Kiev , in Russia , and the more refined paintings of St . Mark ' s , at Venice . There Avas at first much similarity between

glass painting and mosaic painting . The Byzantine mosaics ( of Roman origin ) Avere made of rough cubes of coloured opaque glass , imbedded in cement ; and the earliest stained windows are believed to have been made of small pieces of translucent glass , imbedded also in cement . There are but feAV remains of AvindoAvs of so

perishable a construction . There are some specimens in England that have been brought from the Continent , but are of uncertain date ; and Mr , Surges mentions that the Mosque of St . Sophia , at Constantinople—a Byzantine building of the tenth century—was so glazed , and thafc it is still a custom in the East to make the windows of

glass and cement alone . A great improvement on the use of cement was the method of fastening together the small pieces of translucent mosaic with leaden bands , having * a groove on each side ; and we have to thank the inventor , whoever he may have been , but who

lived somewhere aboufc the twelfth century , for this mode of constructing stained Avindows , very many specimens of AYhich have endured for seven centuries . The construction of a stained windoAV by means of lass and leaden band onlymust have been a

g , itedious work ; and , in time , means were disco - vered for greatly accelerating the process , by making the glass in larger pieces , and by the addition of enamel painting . Take , for instance , the head of a saint : this , "before the introduction of enamel painting , would

have been made up of different coloured glasses —one colour for the hair , another for the beard , and AA'hite glass for the eyes ; the lines of the eyebrows , ears , nose , & cv , would have been expressed by the lines of the leaden bands , Avhich also serve to unite the different pieces of glass .

But , after enamel paintings had been invented , the process would have been this . * a piece of glass as large as the head would be shaped to the required size . The features would then be painted with opaque enamel , and afterwards the glass "would be exposed to a full red heat to cause the enamel to adhere .

The composition of this enamel paint is in glass painting a very important matter . The ancient enamel is in many instances perfect to this day , and occasionall y has preserved from decay the glass itself ; "while in many modern windows ,, after

a few years , it altogether disappears . There are many stained windows , some of them of great repute , executed within the last ten years , that have required nearly as much restoration from this cause as windows of the thirteenth and fourteenth

century . Enamel is composed of a mixture of metallic oxide , and a flux ; this flux answers the same purpose as copal varnish in decorative painting ; it effects the adhesion of the colour to the surface . In the decorative paintings of the Houses of

Parliament , a mixture of copal varnish and turpentine Avas used , and I think it the best material for the purpose . In glass painting , a flux is required that shall melt afc a lower temperature than the glass itself , and that shall not in course of time decay bthe absorption of moisture .

y Borate of soda , potash , soda , or salt , all deliquescent materials , are often used for glasspainters' colour ; and they all , sooner or later , disintegrate through absorption of moisture . A colour that you may trust is composed of red lead , sand , and oxide of iron . Melt for two

hours , at a Avhite heat , three parts of red lead and one part of white sand , and pour ifc into water ; then pound it fine , and mix about four parts of ifc with one of oxide of iron ( Indian red ) or burnt umber , and a little manganese ; grind it vei * y fine Avith a muller on a glass slab , and paint the glass wifch it , using either a little loaf sugar and water , or turpentine mixed with old turpentine that has become thick .

Potash and soda , you are aware , are both used in conjunction with silica in the manufacture of glass ; fche silica and alkali are mixed in such proportion as to neutralise any further action of the alkali . Not so in the flux composed of potash or soda . To obtain the requisite IOAY point of fusion ,

the alkali must be used in excess , and , not being neutral , it will soon become hydrous . The cause of the decay of some of the ancient glass was its having been mixed Avith too great a proportion of alkali , which in course of centuries has absorbed moisture enough to work the mischief .

Afc fche earliest time in the history of glasspainting the pre-existing mosaics appear not only to have suggested the invention of stained windows , bufc to have been the mine Avhence the painters drew some of their materials . There is a striking passage bearing on this point in the

treatise of Theophilus , a translation of which you will find in Winston ' s " Hints on Glass-staining . " Theophilus was a learned and pious monk , who wrote in Greek several treatises , but when , and at what time , no one seems certainly to know ; but , from his perfect knowledge of stained-glass windows , he most probably lived about the thirteenth century .

There are found in the ancient buildings of the Pagans in Mosaic work , different kinds of glass , viz ., white , black , green , yellow , sapphire , red , purple ; and the glass is not transparent , but devise