Abstract: An apparatus for oscillating a test tube so as to agitate the content thereof, comprises an annular holder from which the test tube can be hung by means of a flange located on the upper end of the test tube, in a manner such that the test tube is restricted swingable outwardly in all directions from its vertical rest position. Mounted externally of the test tube bottom is a plate of soft-magnetic material or a plate-shaped permanent magnet with its magnetic axis coinciding with the axis of the test tube. A plurality of electromagnets for example four in number, are stationarily arranged with their respective first poles located in a common horizontal plane at a distance beneath the lower end of the test tube, in a manner such that the poles lie on a circle concentrical about the vertical rest position of the test tube.

Abstract: An arrangement for supplying metered quantities of reagent liquid to a test-tube in a clinical analyzing apparatus, includes a cup for reagent liquid and a pipetting pump which is movable between the reagent cup and the test-tube and which is able to withdraw by suction a given volume of reagent liquid from the reagent cup and dispense said volume of liquid into the test tube. The reagent liquid can be supplied to the cup from a storage vessel, by connecting a source of sub-pressure to the reagent cup and by withdrawing reagent liquid from the storage vessel by suction up into said cup through a line connecting the storage vessel with the cup. The sub-pressure is applied to the reagent cup by means of a bellow structure mounted on the pump so as to be moved into sealing abutment with the rim of the reagent cup when the pump is lowered thereinto. The bellow structure is connected to a source of sub-pressure.