retort-stand

from The Century Dictionary.

• noun A vertical rod, generally of iron, with a heavy metallic foot, and a number of metallic rings, of different sizes, each at the end of a horizontal arm and capable of sliding up and down the rod and of being fixed at any desired height by a pinch-screw: the whole serves to support a retort or other vessel, properly adjusted as to height, over a lamp-flame. Also known as retort-holder or retort-support.