Water-level Small 320×163 Medium 640×326 Large 1024×522 Download Tiff Original 2400×1223 | (256.3 KB) Description The instrument called the water-level illustrates the principle of equilibrium in vessels communicating with each other. Keywords Equilibrium, instrument, Level, physics, water-level Galleries Fluid Mechanics Source: A. Privat Deschanel Elementary Treatise on Natural Philosophy Part I. Mechanics, Hydrostatics, and Pneumatics (New York: D. Appleton and Company, 1884) 119