The invention of glassmaking processes that enable the manufacture of large and relatively cheap panes of glass is fairly recent. Aesthetically, this is fortunate: the availability of only small panes of glass led to the development of intricately crafted leaded lights as a means of forming larger windows and, later, the need to divide wooden casements and sashes with glazing bars.
Glassmaking is an ancient craft with window glass once a valuable commodity. The various methods of blowing molten glass to form panes resulted in the characteristic straight ripples, bubbles, and circular lines that are so alluring
