Every physical theory must be verified by experiments. The spouting can experiment consists of a cylindrical vessel filled up with water and with several holes in different heights. It is designed to show that in a liquid with an open surface, pressure increases with depth. The lower a jet is on the tube, the more powerful it is. The fluid exit velocity is greater further down the tube.
The outflowing jet forms a downward parabola where every parabola reaches farther out the larger the distance between the orifice and the surface is. The shape of the parabola  is only dependent on the outflow velocity and can be determined from the fact that every molecule of the liquid forms a ballistic trajectory (see projectile motion) where the initial velocity is the outflow velocity :
The results confirm the correctness of Torricelli's law very well.