Description
This is a second-stage working technique which was inspired in 1922 by the invention of borosilicate glass, Pyrex, in the United States.
The initial semi-worked object is a borosilicate glass rod, which is reheated on a horizontal flame which comes out of a nozzle fuelled by a mixture of gas and oxygen. Attaching one end of the pipe to a short and thin blow pipe, the lamp craftsman expands the glass and shapes it with small tools.
