Memoirs of the Geological Survey of India, Volume 1

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated.1865 Excerpt: ... other patterns. Among the useful articles may be mentioned watchglasses and double convex spectacle lenses for old or weak sight. Among some specimens of Vellum stones, cut and uncut, presented to the Museum of the Geological Survey of India by W. M. Caddell, Esquire, the Collector of Tanjore, was a crystal of amethyst, (a six-sided prism, with terminal pyramids, ) in which, radiating from the corresponding faces of an internal pyramid, was a brush of small acicular crystals of Rutile. The crystal, which was rather broken at one end, measured one inch in length by 35 in diameter These pebbles and crystals are most likely derived, in the first place, from large quartz veins in the metamorphic rocks. The preparation of vessels of all shapes and sizes from blocks of pot-stone or compact steatite, has already been rePot-stouc vessels. ferred to (see note, page 102). The vessels are cut by means of various chisel-shaped tools, when resting either on a pad of straw and rags, or else on the operator's lap. The profits seem to be but very small, judging by the poverty-stricken appearance of the workers at Tandacoundenoor, &c., which is due probably to the great number of failures they have to contend with, owing to numerous flaws and impurities in the pot-stone. The manufacture of vessels of pot-stone or compact steatite is also carried on at Yermaputty, a village lying near the western end of the great valley separating the Kolymullays from the Tullamullay. In one pit at this place from which pot-stone had been dug, we noticed a small vein of beautiful dark green crystalline Chlorite. The vein varied from 1 to 4 inches in thickness. Trap Rocks are, within our area, used only as rough stones for tank bunds, &c., or as road metal, for which latter Trappean rocks l us...