Kinahan — On Irish Marbles and Limestones. 373 



INTBODUCTION. 



It appears expedient to give, as an introduction to the subject of 

 the following pages, an epitome of the geological and lithological 

 relations of these rocks to one another, and subsequently classified 

 lists and sub-lists — those classed as marbles being separated from 

 those more suited for cut-stone purposes : necessarily, however, 

 most of the marbles are also applicable for more general uses. 



The lists of the marbles will be as complete as possible, and in 

 them will be included all places where stones have been worked as 

 marble, whether successfully or otherwise. To these will be added 

 other places in which stones are found that may possibly be here- 

 after utilized. 



Marbles proper are limestones or metamorphosed limestones of 

 a, nature capable of taking and retaining a good polish. The 

 metamorphosed limestones belong to two divisions — those that 

 have undergone simple metamorphism, that is, have only been 

 altered by the action that affected the associated rocks ; and those 

 that underwent a second or after change, due to chemical action 

 from without (methylosis). These secondarily changed limestones, 

 including dolomytes (ophiolytes, ophicalcytes, dolomytes, &c), are 

 generally called Serpentine ; but under this general name are also 

 included chemically- allied rocks [ophytes, eklogytes, steatytes, pyro- 

 phyllytes, &c), rocks that originally were in general of volcanic 

 origin. It therefore is expedient to include these also under the 

 title of marble, and class them all together, not only on account of 

 their chemical relations, but because all are generally recognised as 

 marbles ; and, if separated, would lead to confusion. As they 

 will be hereafter given in separate sub-lists, and their proper 

 relations to one another be pointed out, there will be no incorrect 

 scientific classification. 



The marbles will be classified as much as possible according to 

 -colour, under the county names, placed alphabetically ; while, at 

 the same time, their geological and lithological positions will be 

 kept separate, and each will be described so as to give a general 

 knowledge of the rocks, and the probability of their being of 

 <economical value. 



