Abstract: A mechanism is provided for varying the distance between a detector and a measuring crystal in an X-ray spectrometer. The crystal is arranged on a rotatable shaft and the detector is arranged on an arm which can perform a circular movement about the crystal shaft. The crystal shaft and the detector arm are coupled so that a rotation of the crystal shaft through an angle .theta. is accompanied by a rotation of the detector arm through an angle 2.theta.. A first pulley having a radius r is mounted on the crystal shaft and a second disc having a radius 2r is rotatably mounted on the crystal shaft. A belt or cord is guided over each one of two guide rollers. One end of each of these belts is permanently connected to the first pulley, while its other end is permanently connected to the second pulley.

Abstract: Apparatus for handling test-sample carriers in the form of elongate rectangular containers, each of which can accommodate a number of test-sample holders to be brought to a treatment station one after the other, comprises a rectangular table having two adjacently situated longitudinally extending zones each provided with a pair of parallel longitudinally extending conveyor belts respectively movable in opposite directions. The containers loosely rest in a transverse position on such belts by means of protrusions provided on their undersides. At the end of each zone, a stop is provided for arresting the containers. For the transverse displacement of the containers, on each end of the table there is provided a pin or roller which is eccentrically connected to a rotatable shaft such that the pin or roller can perform a rotary movement in the plane of the sidewall of a container bearing against the stop and which cooperates with slot-shaped recesses provided in the relevant sidewall of each container.