Savart's toothed wheel apparatus, named alter Felix Savart (1791-1841), a French physicist and surgeon, consists of a brass wheel, whose edge is divided into a number of equal projecting teeth distributed uniformly over the circumference, and which is capable of rapid rotation about an axis perpendicular to its plane and passing through its centre, by means of a series of multiplying wheels, the last of which is turned round by the hand.
Savart (" Memoire sur la constitution des veines liquides lancees par des orifices circulaires en minces parois," Ann.
Savart showed, by a suitable isolation of the reservoir from tremors, whether due to external sources or to the impact of the jet itself in the vessel placed to receive it.
Two laws were formulated by Savart with respect to the length of the continuous portion of a jet, and have been to a certain extent explained by Plateau.
When the head is given, Savart found the length to be proportional to the diameter of the orifice.