This Liquid Glass Medium called CMC (carboxyl methyl cellulose) comes in a powder form. Mix with powdered glass frit (System 96 or Bullseye Glass) and water to make a pourable fusing glass mixture which you can fire in the kiln like a liquid stringer.
Heres how CMC Powder works:
Put the kettle on and boil some water. Pour one pint of boiling water into a container, and add around four or five heaped tablespoons of CMC powder. Stir the liquid well for about 30 seconds. We reccommend you experiment with the proportions of the CMC and water mix which will mean you can control the thickness of your liquid stringer. Leave your CMC mix overnight to cool, by which time any lumps should dissolve and you should have a clear gel. it is best to start with a thicker mix, which you can thin with water if required. If the mix is too thin to begin with, the process must be started again from scratch.
The mix is best applied using s squeezy bottle with a fine point, or a cake decorators bag. Mix with Bullseye or System 96 frit in powder form, and experiment with your quantities to work on depth of colour and transparency. Try a 50:50 mix to begin with. CMC powder burns off cleanly when fired. A tack fuse will leave a raised profile to the line, a full fuse will flatten and fully melt the glass.