288 ROCKS AND MINERALS OF UNITED STATES. 



( Crystal, quartz, amethyst, chalcedony, car» 

 I nelion, cacholong, epidote, asbestos, chaba- 

 Greenstone. \ sie, chlorite, hornstone, calc spar, ores of 

 | iron and copper, zeolite, prehnite, selenite, 

 •S J VLincolnite, &c. 



Ph ] Porphyry. Gold, specular oxide of iron. 



i L Epidote, feldspar, amethyst, zircon, fluate of 

 Syenite. < lime, quartz, lead, zinc, copper, titanium, ba 

 ( rytes, hypersthene, arragonite, chabasie, &c. 

 ( Fluate of lime, phosphate of lime, calcareous 

 I spar, argentine, ores of copper, iron, lead, zinc, tin, 

 Granite. \ manganese, molybdena, titanium, barytes, sulphur, 

 I quartz, amethyst, pinite, topaz, chrysoberyl, mica, 

 V feldspar, schorl, beryl, garnet, staurotide, talc, &c. 



Note. — In forming the following table we have consulted all the 

 authorities within our reach. But we acknowledge our particu 

 lar obligations to the masterly reports of Prof. H. D. Rogers, of 

 Pennsylvania, and of Messrs. Conrad, Vanuxem, and the other 

 geologists of this state, who are in a fairway to reduce to some- 

 thing like order the hitherto chaotic formations of this country. 



It will be seen from the opposite table that the highest strata 

 in the State of New- York are the conglomerates which form 

 the highest portion of the Catskill Mountains, which, according 

 to Professor Rogers, is more than 3000 feet below the coal meas- 

 ures of Pennsylvania. 



For the thickness of the rock formations of Pennsylvania, the 

 reader can consult the table on page 242, where the numbers cor- 

 respond to those in the present table. 



* The sandstones and conglomerates of Catskill Mountains 

 probably belong to the old red sandstone group of Murchison. 



f Professor Conrad, in his " Report," &c, states that this 

 group, consisting of olive sandstone and slate, cut through by Sal- 

 mon River, together with the preceding red sandstone group, corre- 

 sponds in geological position with the fourth group in the slate 

 system of Wales, described by Prof. Philips. But this appears 

 to us a mistake, as the whole of the four groups described by 

 Philips belong to the clay slate system, and lie below the lower 

 silurian system, which consists of the Llandeilo flags and lime- 

 stone. This will appear from Mr. Conrad's own statement, that 

 the black limestone and shale of Trenton Falls {lying below) cor 

 respond in position to the black shale enclosing beds of gray 

 wacke, flagstone, &c, which are joined to the Llandeilo flags. 

 We have made this formation correspond with the Wenlock 

 limestone and slate above the Llandeilo flags. 



