Page:Popular Science Monthly Volume 27.djvu/541

Rh quarried at Mount Desert, in the same State; Lyme and Stony Creek, Connecticut; Westerly, Rhode Island; and Graniteville, Missouri. The Calais rock, which is at present the most important of these, is a light pink in color, of medium coarseness of texture, and acquires beautiful surface and polish. It is used extensively for door-posts and the bases of monuments in all our principal cities, competing favorably with the coarser red granite from Peterhead, Scotland, or that from St. George, New Brunswick.

Black granites are quarried in but two, and these widely separated, localities—St. George, Maine, and Penryn, California. Both stones are fine-grained, and nearly black on a polished surface, their dark colors being due to the abundance of black mica and hornblende that they contain. The greater part of the rock quarried and put upon the market under this name is, however, not granite at all, but diabase, a rock differing from granite in containing neither quartz, orthoclase, nor mica, but composed mainly of a triclinic feldspar and augite. The principal quarries of this rock are at Addison, Maine; Medford and Somerville, Massachusetts; York, Pennsylvania; and near Jersey City, New Jersey.

These rocks are all fine-grained and hard, and of a dark-gray color, that from Addison being nearly black when polished. The colors are rather too somber for general building purposes, but, when properly combined with brick or lighter stone, the effect is admirable. The Addison rock is being used to a considerable extent for cemetery and other monumental work, for which it seems peculiarly adapted, and together with the York diabase has been used in the stone-work of the Capitol-grounds at Washington. Diabase from the near vicinity has been used in the construction of the Stevens Institute building at Hoboken, New Jersey, and the court-house and St. Patrick's Cathedral at Jersey City. The fronts of many private and business houses in the last-named city are also of diabase, but the effect is not good, owing to the somber colors already alluded to.

From the fact that Maine and Massachusetts lead in the granite quarrying industry, it does not necessarily follow that these States produce a greater variety or better quality of material than some others in which the annual product is far less. The supremacy is due rather to natural quarrying and transportation facilities. In Maine especially many of the quarries are situated on hill-sides close by the water's edge, where no artificial drainage is required, and but little carting of the stone is necessary prior to loading it upon vessels, by means of which transportation can be had to all the leading cities of the country without transhipment, an item of no small importance with material so bulky and heavy as stone. Added to this is the fact that the great glacial ice-sheet, that once plowed its way across the whole of New England, has entirely removed the overlying mass of decayed rock and other waste material, and left the fresh granite close to the