Editing National Library of Ireland (section)

===Structural decay===
By 1993, the Mount Charles sandstone which had been used to [[Stone veneer|face]] the library building (as well as that of [[National Museum of Ireland – Archaeology]]) had begun to break up through the "precipitation of salts within the fabric of the rock".{{sfn|Wyse Jackson|1993|page=12}} The sandstone had been badly affected by the coal-polluted atmosphere in Dublin over the century it had remained in situ, and was replaced in the 1960s by a grey limestone from [[Ardbraccan]], [[County Meath]].{{sfn|Wyse Jackson|1993|page=35}} As of 1993, Wyse Jackson noted that "Close examinations of the stone remaining on the National Museum shows obvious decay and exfoliation of the outer layers of the rock, caused by the breakdown of the ferrous cement used to bind the sand grains together".{{sfn|Wyse Jackson|1993|page=35}} Wyse Jackson made the note that the same rock had not been broken down by the atmosphere or pollutants in its native County Donegal where a number of buildings constructed as early as 1820 were still extant.{{sfn|Wyse Jackson|1993|page=35}}