A fabulous set of three antique Lab Lenses. 
Ebonised turned wood frames and stands two smaller with magnifying lenses in and the larger with a tinted convex mirror. 
They have had a hard working life in the lab and show signs of this with a little damage to two of the lenses, which I have shown in the last two photos, however they’re still fabulous things and good fun too. 
Measurements:
Large: 29cm high, frame 13cm diameter 
Medium: 22cm high, frame 9cm diameter 
Small: 15cm high, frame 7.5cm diameter