Publisher's Synopsis
This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1837 edition. Excerpt: ... EXPLANATION OF GEOLOGICAL TERMS. It has been thought advisable to give, at the end of this Report, a brief glossary of such terms as cannot be found in the ordinary dictionaries, such terms having no common English synonymes. Alluvium, consists of clay, sand, and gravel, washed from the surface of hills and mountains, they being transported by currents of water, such as torrents, rivers, and brooks, from the high lands and deposited along their course. Etym. alluo, to wash upon. Amorphous, a word derived from the Greek, signifying without regular form. Amygdaloid. One of the forms of trap-rocks, the trap being full of rounded holes filled with various minerals, bears some resemblance to an almond cake, and the name is derived from the Greek, signifying, like almonds. Amtgdaloidal Trap, is produced by the contact of trap with other rocks, where a chemical action was exerted, and the trap being in a molten state, was blown into a scoria-like form, by the gasses or steam disengaged. The cavities are generally filled with infiltrated minerals, such as calcareous spar, chlorite, agate, &c. Similar appearances are seen in lavas of modern volcanoes, and they may be produced at will in the slag of any iron furnace, by allowing the slag to run over moistened sand. Various forms of lava may thus be produced, from the compact and glassy obsidian to perfect pumice stone. Andalusite, a mineral consisting of alumina, silex, and a little oxide of iron, found first in Andulusia in Spain--hence its name. Anthracite, is a very hard kind of coal, destitute of bitumen. It burns without smoke and with very little flame. Its name i from the Greek, signifying coal. Apophtllite, a simple mineral sometimes called fish-eye stone. Argillaceous, means...
