On what equipment and how is the experiment shown in Figure 50 carried out? What physical phenomenon

On what equipment and how is the experiment shown in Figure 50 carried out? What physical phenomenon is demonstrated in this case, what is it and what physical law is the basis of this phenomenon? Note: The rubber tube was positioned vertically until water was passed through it.

A funnel was attached to the tripod using a holder with a rubber tube attached to it from below with a curved nozzle at the end, and a tray was placed below. Then, water was poured from the top into the funnel from the container, while the water was poured from the tube into the tray, and the tube itself shifted from a vertical position. This experience serves as an illustration of jet propulsion based on the law of conservation of momentum.