56 Proceedings of the Royal Irish A cademy. 



The few undoubted pieces of Irish glass which have been foimd stamped 

 with the name of a particular glass house are of a clear metal, without any 

 trace of the blue tint, though not so white as modern glass. An analysis of a 

 piece of glass having this blue tint gives the following composition : — 



Lead oxide ... ... ... 36-56 



Potash ... ... ... ... 8-48 



Soda ... ... .. ... 3-08 



SUiea, including traces of other oxides . . . 51"88 



10000 



There is no trace of cobalt, to which some attribute the blue coloiu-. 



The metal of Irish and EngHsh flint glass was made fi-om practically the 

 same materials, the sand being obtained chiefly from the Isle of Wight, though 

 the glass house at Dmmrea, near Dungannon, used local sand. 



Sand for bottle glass was obtained in Ireland — that for the Dublin glass 

 houses from the Xorth Bull ; for Cork, probably from Youghal and Tramore ; 

 and that for Ballycastle, from the immediate neighbourhood. 



It is said that ships trading between the South of Ireland and France 

 often brought back sand as ballast ; but whether this sand was used in the 

 manufacture of glass either in Cork or "Waterford is uncertain. 



Again, the patterns on Irish and Enghsh cut glass are very similar, which 

 may be accounted for by many of the proprietors of Irish glass houses being 

 Englishmen, and also from the fact that glass was cut in Ireland by EngHsh 

 workmen. 



Benjamin Edwards, who managed the glass houses at Drumi-ea and Belfast, 

 came from Bristol, and probably earned on the manufactm-e in the same 

 manner as in the latter town. The only records of enamelled glass in Ireland 

 which appear as late as 1801 occur in connexion with these two factories, 

 and this special kind of glass was lai^ely made in Bristol. 



Diamond-cut glass is mentioned as ha\'ing been imported into Ii-eland from 

 England in 1747 : but it was probably not until somewhat later that much 

 cutting was employed on Irish flint glass. 



Cut and flowered glasses, and diamond-cut cruets are mentioned in 1752 

 as having been made in the Mary's Lane glass house, and also glasses engraved 

 with vine borders, toasts, &c. 



The various patterns cut on Irish glass were probably largely copied from 

 those employed in England ; and, as far as can be ascertained, the earlier 

 pieces had less cutting than those of later date. Pieces with shallow-cut 

 wreaths, and broad, low nail-head cutting, are supposed to be the earher 

 forms of decoration ; still no definite rule can be laid dowTi, as pieces of the 



