glaserian

(gla-se’re-an) [named for or described by Johann He in rich Glaser (Glaserius), Swi anatomist, 1629-1675]. See under fi ure, etc. A hard, brittle, and often transparent substance, usually consisting of the fused amorphous silicates of pota ium or sodium, and of calcium, with silica in exce . crown @., a hard gla ; a silicate of sodium (or pota ium) with lime and alumina. flint g., a soft gla , mainly composed of lead and pota ium silicates. soluble g., water g., a pota ium or sodium silicate: somewhat in use in preparing immovable bandages. See spectacles. bifocal g., Franklin g., those which have two different refracting powers, one in the upper and the other in the lower part of the lenses. rbolic g., those ground with a section of a hyperbolic curve. periscopic g. See under Jens. pr: tic g., are made of prisms, and are used in paralysis and insufficiency of the ocular muscles. snmow-g., spectacles worn to prevent snow-blindne . stenopaic g., a form having a narrow slit or a small hole in a blackened disk: used in examining for astigmatism. Resembling gla ; hyaline or vitreous.