Fining of Glass

R. G. C. Fining of Glass Melts What we Know abtmiFining Processes Today. 

Appendix D Falling Sphere Viscometer and Fining of Glass... 

T for attachment to the angle tube F. The tap T, niay have a length of glass rod fused to it so that it is capable of fine adjustment. The lower (internal) end of the capillary tube G is bent downwards and is also drawn out very slightly. 

The solid in the tower may be supported on a Witt filter plate, but a plug of glass wool is satisfactory the plug of glass wool above the solid acts as a filter for fine particles of the desiccant. 

Solid magnesium must be absent to avoid the formation of diallyl via allyl magnesium bromide the insertion of a short plug of glass wool effectively removes any finely divided magnesium. 

Lead oxide is used in producing fine "crystal glass" and "flint glass" of a high index of refraction for achromatic lenses. The nitrate and the acetate are soluble salts. Lead salts such as lead arsenate have been used as insecticides, but their use in recent years has been practically eliminated in favor of less harmful organic compounds. 

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