Fig. 42.
Fig. 43.
Fig. 44.
And the first is to fire it enough. Whatever pigment you use, and with whatever flux, none will be permanent if the work is under-fired; indeed I believe that under-firing is far more the cause of stained-glass perishing than the use of untrustworthy pigment or flux; although it must always be borne in mind that the use of a soft pigment, which will "fire beautifully" at a low heat, with a fine gloss on the surface, is always to be avoided. The pigment is fused, no doubt; but is it united to the glass? What one would like to have would be a pigment whose own fusing-point was the same, or about the same, as that of the glass itself, so that the surface, at least, of the piece of glass softens to receive it and lets it right down into itself. You should never be satisfied with the firing of your glass unless it presents two qualifications: first, that the surface of the glass has melted and begun to run together; and second, that the fused pigment is quite glossy and shiny, not the least dull or rusty looking, when the glass is cool.
"What one would like to have."