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. Encyclopaedia; or, A dictionary of arts, sciences, and miscellaneous literature; constructed on a plan, by which the different sciences and arts are digested into the form of distinct treatises of . C b ca being allin the fame inclined plane, which is the cafe with theother three homologous figures. Now, in order toinveftigatc the formation of thefe cryftals, let us fup-pofe the rhombi CO, CP, and C Q^, to be comple-ted, which to an eye placed in the high axis C, willappear like as many fqnares fituated in the fubja-cf nt plane. Thus we may underftand the formationof the cryftals o
. Encyclopaedia; or, A dictionary of arts, sciences, and miscellaneous literature; constructed on a plan, by which the different sciences and arts are digested into the form of distinct treatises of . C b ca being allin the fame inclined plane, which is the cafe with theother three homologous figures. Now, in order toinveftigatc the formation of thefe cryftals, let us fup-pofe the rhombi CO, CP, and C Q^, to be comple-ted, which to an eye placed in the high axis C, willappear like as many fqnares fituated in the fubja-cf nt plane. Thus we may underftand the formationof the cryftals of granite as well as of the former may be ftippofed a quadrangular prifmcompofcd of four rhombi, touching one another onlyat their apices, and terminated at each end by fourrhombi meeting at the apex. When this form is alittle protracted, or augmented by applying to theapices, fimilar and equal planes, it becomes that of thehyacinth; whence the granite cryftal maybe calledthe rudiment of the hyacinth alfo. The varictv here mentioned II Deviation*from a per-fcdl cryltal-linc form. Triangularcryftals. garnetcryllal. J*Cruciformhyacin-thine cry-llal. ^>^^.
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Keywords: ., bookcentury1700, bookdecade1790, booksubjectencyclo, bookyear1798