Abstract: An apparatus for applying a liquid sample onto a culture medium in a spiral shape, for example, for determining the bacteria concentration therein, having a line that has an incline nozzle for applying the liquid sample onto the culture medium. A turntable supports a culture medium container and the line is supported by a linearly movable slide. The position of the nozzle relative to the turntable is automatically adjusted in response to a signal from a sensor, which detects the level of the upper surface of the culture medium. An automatically controlled movement mechanism, together with a level control device or a disinfecting container, insures that the nozzle is submerged deep enough into the disinfectant to properly disinfect the outer side of the nozzle.