[System of temporary blocking of transporting device of the universal automat of the AT-4 type for histological handling and staining of tissues].

A rapid transfer of the box with tissues from vial to vial by the AT-4 automate (10 seconds) results in premature contamination of the subsequent reagent with previous one causing excessive use of scarce and expensive reagents. A system of temporary blocking of the transporting device is described which permits one to arrest the box above the vial for 30 sec in which time all the reagents flows back into the vial from the box. The use of the blocking of the transporting device for 360 sec in each cycle of tissue staining (12 vials) does not reduce the working capacity of the AT-4 apparatus but markedly saves the amount of reagents used and improves the quality of treatment.