Abstract: Apparatus for, and a method of, automatic chemical analysis. The apparatus comprises a conveyor system for delivering vials containing samples for analysis through an entry gate and identification arrangement to a series of analytical modules where a succession of tests is effected on each of the samples. Each of the analytical modules comprises a sample probe, a reagent probe, a container for reagent adjacent to the conveyor means, a movable stop member arranged to hold a vial in an appropriate position adjacent to the module, means for moving the movable stop member so as to allow the vial to pass from one module to the next, and means for moving the sample and reagent probes between a first position where they are ready for insertion into a vial, and a second position where they are held clear of the vial. The apparatus also includes synchronizing means arranged to co-ordinate operation of the various elements of the apparatus.