They can produce a great variety of glass objects , ranging from drinking cups to window glass .
Skilled workers are capable of shaping almost any vessel forms by rotating the pipe , swinging it and controlling the temperature of the piece while they blow .
workers can produce a great variety of glass objects , ranging from drinking cups to window glass .
Skilled workers are capable of shaping almost any vessel forms by rotating the pipe , swinging it and controlling the temperature of the piece while they blow .