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Crystal Model
A crystal model is a teaching aid used for understanding concepts in crystallography and the morphology of crystals. Models are ideal to learn recognizing symmetry elements in crystals. Romé de l'Isle The first real collections of crystal models were produced by Romé de l'Isle. He actually offered sets of small (ca 3 cm) models made of "terra cotta" in order to stimulate the sales of the expensive 4 volume set of his book "''Cristallographie''" (1783). The models were manufactured by his co-workers Arnould Carangeot, Lhermina and Swebach-Desfontaines, who produced numerous large sets (up to 448 models in each set). In order to exactly transfer interplanar angles from natural crystals to the terra cotta models, Carangeot invented and designed a prototype of a contact goniometer. This instrument, that proved to be an invaluable tool in geometric crystallography, enabled the measurement of interplanar angles with a precision of about half a degree. Teylers Museum in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arnould Carangeot
Arnould Carangeot (12 March 1742 – 16 December 1806) was a French naturalist and mineralogist who invented one of the first Goniometer, goniometers for measuring the angles of the faces of crystals. Through its use came about the first ideas in crystallography on the constancy of the dihedral angles and symmetry of crystals of specific chemicals. As an assistant to Jean-Baptiste L. Romé de l'Isle, Jean-Baptiste Romé de L'Isle he examined crystals to make clay models and invented the goniometer in 1780. This led to Romé de L'Isle establishing the rule of constancy in the form of symmetry, a slight advance over Nicolas Steno, Steno's idea that the interfacial angles were constant for a given substance. He also contributed to a work on the butterflies of Europe. References External links Papillons d'Europe peints d'après nature (1779-1792) {{DEFAULTSORT:Carangeot, Arnould 1742 births 1806 deaths French naturalists ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
