NEALING of glass, is the baking of glass, to dry, harden, and give it the due consistency, after it has been blown, and fashioned into the proper works.—This is usually performed in a kind of a tower called the leer, built over the melting furnace. See GLASS.
Nealing of glass is also used for the art of staining glass with metalline colours. "One fine use of silver (says Mr Boyle) was only discovered since the art of annealing upon glass came to be practised. For prepared silver, or even the crude metal, being burnt on a glass plate, will tinge it of a fine yellow or golden colour. And there are several mineral earths, and other coarse matters, of use in this art, which by means of fire impart transparent colours to glass, and sometimes very different ones from those of the bodies themselves.