282 Dr. Mac CvLLOC a on ihc Geology of Glen Tilt, 



quainted with the beautiful stone of Carrara, have confined their 

 labours to this more perfect variety. It is however perfectly appli- 

 cable to various architectural as well as oeconomical objects. A 

 marble perfectly similar to it has lately been imported from 

 America for the same purposes, to many of which its greyish hue 

 and low tone of colour are more applicable than the dazzling 

 white of Carrara. It is of a larger grain and a more compact tex- 

 ture than the Pentelic, with which the beautiful and interest- 

 ing remains imported by Lord Elgin have lately made us acquainted. 

 But the Pentelic marble, like that of Glen Tilt, contains mica, 

 and from this contamination arises its fissile nature, to which we 

 unhappily owe so much of the injury which these wonderful 

 works have suffered. When polished, the two can scarcely be 

 •distinguished from each other ; the difference in the size of their 

 grains disappearing, and the grey and watery stains, with the 

 brown stripes of the micaceous laminse, equally characterizing 

 both. 



The discovery of statuary marble in the British dominions has 

 been long a desideratum, but having already in the present volume 

 discussed this question, I shall only briefly remark that how much 

 soever we may admire those wonderful sculptures by Phidias which 

 have been executed in a marbk scarcely differing in colour or quality 

 from this of Glen Tilt, we are very well assured on examining the 

 progress of art in Greece, that the marble of Pentelicus was only 

 used in the deficiency of a purer and more uniform stone, and that 

 it was abandoned when later discoveries had made the sculptors of 

 that country acquainted with a better class of marbles. It would 

 be a fruitless attempt to introduce the marble of Glen Tilt, or even 

 those whiter varieties which Scotland produces, in competition 

 -with the exquisitely beautiful and easily wrought stone of Carrara, 



