"Red heat" Quotes from Famous Books
 ... of large diameter or thin wall is to be cut, it is often better not to attempt to break it in the usual way, but to heat a very small globule of glass (1/16 to 1/8 inch diameter) to red heat, and touch it to the scratch. This will usually start the crack around the tube; if it has not proceeded far enough, or has not gone in the desired direction, it may be led along with a hot point of glass. ...
— Laboratory Manual of Glass-Blowing • Francis C. Frary |
