Surface Tension Balance, Searle’s

For determition of surface tension of liquids. Comprises a metal bridge attached to a vertical rod, which in turn is mounted on pillar of a heavy cast metal stand adjustable for height and has leveling screws. Across the two arms of U-shaped bridge, a steel torsion wire is fixed with provision for adjusting its torsion. A pan is hung from a notch in the pointer and has a hook at its underside from which can be suspended a light weight rectangular frame or a metal clip to hold a micro slide edge. The tip of the pointer moves over a graduated scale mounted vertically on the end of arm fitted to the bridge. With rectangular wire frame, slide clip, six micro slides and spare length of torsion wire. The sensitivity of the balance depends on the modulus of elasticity of the torsion wire. Wire of different diameter will provide different sensitivities.