512 Scientific Proceedings, Royal Dublin Society. 



redressing, or painting, or otherwise doctoring of the stones induce expenses which in a 

 short time eat up any little saving there may have been at the first in using inferior 

 material. This can also be seen in different places in Dublin, which need not now be 

 mentioned, as this subject will be alluded to further on. 



In general, sandstone now in use, except the Caenstone, does 

 not appear to be capable of receiving as minute work as limestone. 

 However, if we examine the old structures, we find in some of 

 them beautiful and elaborate work, but in such cases the stones 

 are much harder than those now in request. The exquisite door- 

 way of Maghera Church, Co. Deny, cut in the local stone, is so 

 durable, that the brushing of the tools can still be seen ; but 

 this stone would not now be looked at, being considered "too 

 hard." 



According to the records, as left by our ancient buildings, it 

 would appear that the soft and more easily worked limestone, 

 sandstone, and granite, are best for inside work ; but if the work 

 is to be exposed to weathering, the durability depended on the 

 quartzose nature of the stones, they ranging in the following 

 order — quartzose sandstone, quartzose limestone, and quartzose 

 granite. The sandstones, apparently, taking in our climate the 

 first place. 



There are, indeed, in a few places very quartzose granites and 

 limestones of a high order, but they are exceptions to the general 

 rule, as the majority of our best preserved old work nearly inva- 

 riably is in sandstone. Outside these groups there are, however, 

 some stones, but not very commonly met with, that show durable 

 work, such as the Camstone, and some of the basalts. 



Quartzose stones, when dry, nearly invariably are difficult to 

 work. This is the case with the " Park stone," Wexford, which, 

 when worked in its " quarry water," as exemplified in Roche's 

 Churches, turns out good work. Our ancestors may have under- 

 stood this peculiarity in the stones, or it is possible they may have 

 overlooked first- costs, and speculated solely on the subsequent 

 durability of their work — they working in hard stones that now 

 would be condemned. 



[Some sandstones which occur not uncommonly in the Carboniferous formation 

 have a latent silicious or carbonaceous cement, and when newly raised, and in their 

 quarry water, are soft and easily worked, but subsequently, when dry, they become as 



