Attach 125 ml separator thru 24/40 joint to third neck of distg flask. Attach piech of robber tubing to short U-tube in serted thur rubber stopper in neck of separator. Blow in to rubber tubing, and close separator stopcock. Let stand for few min to check for leaks shown by liqs leveling in U-tubes.
Place distg flask in heating mantle controlled by variable transformer. Note; Top of concentrator flask (B) is open to the atmosphere.