Abstract: The invention relates to tower coolers in which the exchange of heat between the liquid to be cooled and the atmospheric air takes place in cross-flow, in plural successive heat exchangers. Liquid leaving a first exchanger is homogeneously mixed before passing to the next exchanger. This may be effected by a device comprising a first compartment sited beneath a first exchanger so as to receive the liquid which falls from said first exchanger. A spillway is placed at one end of said compartment in such a manner that the liquid is displaced therein in a first direction, either that of the airflow or the reverse direction. A second compartment is placed beneath the first and communicates therewith via the spillway such that the liquid is displaced therein in a second direction opposite to the first. Means are provided for discharging the liquid from the second compartment toward the following exchanger.