A popular treatise on gems, in reference to their scientific value; a guide for the teacher of natural sciences, the jeweller, and amateur: together with a description of the elements of mineralogy, and all ornamental and architectural materials .. (1859)
Feuchtwanger, Lewis. [from old catalog] · New York, D. Appleton & company · leaf 76
triclinohedric felspars this sec-tion is not, as it is in the monoclinohedric species, perpen-dicular to the basis, and consequently the two bases formon one side a re-entering, on the other a salient angle;whereas in the monoclinohedric felspars (where the brachy-diagonal chief section corresponds… … m rl\ ^>Z^^^r^ fr\^ \ ) / 1 ^^ ^-•v l! 1; >Wl ^: Mjz VV \.t- VjVpN ( / \k V \/ Fiff. 92. very obtuse angles formed by the faces of OP, or P and P(as well as those of Poo, or x and a?), are a very charac-teristic appearance; marking out this mineral at once as atriclinohedric species. Usually…
Precious stones · Building stones · Mineralogy
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![An illustration from Nicolai Copernici Torinensis De reuolutionibus orbium coelestium, libri VI : Habes in hoc opere iam recens nato, & aedito, studiose lector, motus stellarum, tam fixarum, quàm erraticarum, cum ex ueteribus, tum etiam ex recentibus obseruationibus restitutos: & nouis insuper ac admirabilibus hypothesibus ornatos. Habes etiam tabulas expeditissimas, ex quibus eosdem ad quoduis tempus quàm facillime caculare poteris. Igitur eme, lege, fruere. [Line in Greek] (1543)](https://img.insideoutlibrary.com/img/200/ia-nicolaicopernici00cope-166-93.webp)
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