Page:Narrative of a survey of the intertropical and western coasts of Australia, Volume 2.djvu/632

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GzoLo(?.] NATURAL H!gTORY. riO7 very nearly resembling specimens from d?e trip rocks* of the Wrekin and Breeden Hills in $hropshire. Reddish and yellowish M?dy day, coloured by oxide of iron, and used a? pigments by the natives. Pzz?y Ism, about one hundred and forty miles north of Cape Capricorn.--Compact febpar of a flesh-red hue, enclosing a few small crystals of reddish felspar and of quarts.--This specimen is marked "general character of the rocks at Percy Island," and very much resembles the como pact felspar of the Pentland Hills near Edinburgh, and of Saxony. Coarse Porpk?ritic conglomerate, of a reddish hue. �?0e?t/ne. A trap-like compound, with somewhat the peet of serpentine, but yielding with difficulty to the knife. --This specimen has, at first sight, the appearance of a con- �e.rate, made up of portions of diKerent hues, purplish, brown, and green; but the coloured parts are not other- wise d/stinguisbeble in the fracture :--It very strongly re- semble? a rock which occurs in the trap-formation, near Lyd-Hole, at. Pont-y-Pool, in Shropehire. ? c/al, with particles of mica, like that which frequ?ntll occurs immeo diately beneath beds of coal �By the ter? Trap, ?nd Trap-f?w?io=, wl6eh I m aware ? ex?mely vague, I jutend merely to ?g?ify �ch? of including several members, which differ from each other eonskler- ?,bly in mineralogiczl character, but ?,ree in ?ome of their prino cipai geological relations; and the origin of which very numerous phenomena comur in referri? to some modifieatiou of volestalc agency. The term Green-,to?e also is of very locze &pplic.?tion, and includes rocks that exhibit �wide range of characters ;- the predominant colour being some shade of green, the structure more or less crystaIllne, and the chief ingredients suppo ?ed to be hornblende ?nd felspar,'--but the components, if they could be �ceurately determined, probably more numerous and varied, than systematic lists imply.