To demonstrate the Bernoulli effect produced by water flow. Comprises a Bernoulli tube, with central constriction, a constant bore gradient tube, 6 length glass tubing, 2 swan-necked outlet tubes and 8 pre-cut lengths of rubber connecting tubing. The 2 flow tubes, each 500x13mm, length 25mmx150mm spacing, extended to form 500mm manometer with the lengths of glass tubing.