Boyle's law Apparatus has an improved pattern, mercury reservoir held in clamp sliding on iron rod chrome plated. The wooden scale has vertical reading one meter long, with heavy iron base painted and is also provided with leveling screws. The apparatus comes complete with a set of hard glass tubes without mercury reading they are one meter long with heavy iron base painted, provided with leveling screws. Boyle's Law Apparatus is offered with a set of hard glass tubes without mercury.