from the Museum of the Royal Irish Academy. 339 



But for the contained air bubbles it would have been nearly transparent. The 

 colour was due to oxide of copper ; and both in the staining of the glass, and in 

 forming the bead, the specimen was a very rude result of early art. 



No. 4 was a flattened bead, also from Kilmainham. It was more nearly 

 transparent than any of the others, and had only a very faint tinge of sea-greoti, 

 so pale that it probably was not intentional ; on the contrary, this would seem 

 more likely to have been an attempt at colourless glass, which we know was 

 more highly valued by the ancients, at least in the south of Europe, than any 

 other. I could detect no colouring metallic oxide in the present specimen, 

 except the merest trace of oxide of iron. 



No. 5. An opaque, white bead, of a flattened form, from the same locality 

 with the last. On examination it proved not to be glass at all, but pure crys- 

 talline white marble (carbonate of lime), which had been very neatly cut to the 

 required shape, and the surface well polished. This material has not, I believe, 

 been hitherto noticed among those employed for these primitive ornaments. 



The results of the examination of these glasses agree very well with those 

 of some of the specimens of Klapeoth and Sir H. Davy ; but further inves- 

 tigation of tlie Celtic articles (and indeed of those from the south of Europe) 

 would be important in order to elucidate the history of this ancient manu- 

 facture, as it is only from the analysis of numerous examples, varying in date 

 and locality, that we can hope to derive any valuable general information on 

 the subject. 



Another highly interesting branch of an inquiry as to the means of decora- 

 tion possessed by the ancients is that concerning their 



PIGMENTS, 



and hence I have been most anxious to examine such remains of this kind as 

 might be in existence in Ireland ; but have only succeeded in obtaining speci- 

 mens (used in fresco painting) from a single locality, namely, Slane Abbey, in the 

 county of Meath ; and these probably do not belong to an earlier date than 

 1512, as the Abbey, originally established in the seventh century, was re- 

 founded in that year. These specimens were not contained in the Aca- 

 demy Museum, but were detached by Mr. F. W. Burton, a member of the 

 Academy, and presented for the purposes of this examination. There were 



VOL. XXII. 2 T 



