Page:Transactions of the Geological Society, 1st series, vol. 3.djvu/116

 present corroded and tarnished state of the surfaces of these statues we cannot trace the nature or the defects of this variety, but an examination of its texture and composition in the broken fragments, serves to excite the deepest regret, that the genius of the greatest sculptor whom the world has seen, should for want of better materials have been condemned to bestow its energies on so perishable and so defective a stone. This marble is of a loose texture and moderate sized grain, coarser than that of Carrara, but finer than that of Paros; in colour it is exceedingly imperfect, being tinged with gray, brown, and yellow, and mottled with transparent parts, which give it the appearance of having been stained with oil. But its most formidable defect is its laminated structure, and the quantity of mica with which it is contaminated: to this we are to attribute the corrosion and almost entire ruin of so many of the specimens, the action of the weather dissolving those parts of the stone where the mica is most abundant, and eating deep fissures through many parts of the work. It is peculiarly unfortunate that the two most admirable specimens, specimens which are calculated to excite in the minds of artists a mixed feeling of wonder and despair, the horse's head and the Theseus, should be those which have suffered most. Had they been fortunately executed in the more uniform and durable stone of Carrara, these works might still have been preserved to us in all, their original perfection of drawing and surface. Even the hammer of the Turk would have rebounded with little injury from the marbles of this texture, while the micaceous stone of Pentelicus splitting in the direction of its laminæ, has permitted the complete mutilation of many valuable sculptures.

We have no geological information with regard to the relations of these stones. The great resemblance of the Pentelic marble to