Heaping water up in a glass
Place a drinking glass in a shallow pan or on a saucer. Rub the top edge of the glass with a dry cloth. Pour water into the glass unless it is full to the brim. You will observe that you can fill the glass various millimetres above the top. Now drop coins or thin metal washers under the water edgewise. See how distant you can heap the water up by dropping these in before it runs over.