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Fluor spar; -- so called by Cornish miners.

A mineral of a greenish yellow color; it is a silicate of glucina, lime, and soda with fluorine. Called also leucophanite.

ng the residue. It is a yellowish, fatlike mass, transparent in thin layers, and somewhat fluorescent. It is used as a bland protective dressing, and as a substitute for fatty materials in ointments. U. S. Pharm.

n, C14H10, found in coal tar, and obtained as a white crystalline substance with a bluish fluorescence.

color and a pearly luster. It is a silicate of aluminia, with magnesia, potash, and some fluorine. It is characteristic of crystalline limestone or dolomite and serpentine. See Mica.

ith phthalic acid, and well represented by phenol phthaleïn. Their alkaline solutions are fluorescent. Phenol phthalein, a white or yellowish white crystalline substance made from phthalic acid and phenol. Its solution in alkalies is brilliant red, but is decolorized by acids, and as this reaction is exceedingly delica…

Fluorine. [Written also phthor.]

variety of colors, as certain solutions derived from vegetables, which display colors by fluorescence.

Esculin; -- so called in allusion to its fluorescent solutions. [R.]

A pseudomorphous crystal, as a crystal consisting of quartz, but having the cubic form of fluor spar, the fluor crystal having been changed to quartz by a process of substitution.

A picture produced by the Röntgen rays upon a sensitive surface, photographic or fluorescent, especially a picture of opaque objects traversed by the rays.

A fluoride of alumina and soda occurring with the Greenland cryolite in octahedral crystals.

is capable of passing through many bodies opaque to light, and producing photographic and fluorescent effects by which means pictures showing the internal structure of opaque objects are made, called radiographs, or sciagraphs. So called from the discoverer, W. C. Röntgen. -- X ray, the Röntgen ray; -- so called by it…

ash. It is also produced artificially and used in making certain dyestuffs, as phthaleïn, fluoresceïn, and eosin.

many opaque substances, as wood and flesh, their action on photographic plates, and their fluorescent effects. They were called X rays by their discoverer, W. K. Röntgen. They also ionize gases, but cannot be reflected, or polarized, or deflected by a magnetic field. They are regarded as nonperiodic, transverse pulses…

A hydrocarbon (C13H10) obtained in white fluorescent crystals, in the distillation products of the needles of the California "big tree" (Sequoia gigantea).

adjectively) denoting the presence of silicon or its compounds; as, silicobenzoic, silicofluoride, etc.

nonmetallic mineral, usually cleavable and somewhat lustrous; as, calc spar, or calcite, fluor spar, etc. It was especially used in the case of the gangue minerals of a metalliferous vein. Blue spar, Cube spar, etc. See under Blue, Cube, etc.

small instrument containing a minute particle of a radium compound mounted in front of a fluorescent screen and viewed with magnifying lenses. The tiny flashes produced by the continual bombardment of the screen by the a rays are thus rendered visible. -- Spin*thar`i*scop"ic (#), a.

ell. Temse bread, Temsed bread, Temse loaf, bread made of flour better sifted than common fluor. [Prov. Eng.]