then calculates therefrom a working choice which determines the metering heads toward which the monolith 1 is to be moved and the sequence of this operation beginning with the largest zone 2 the monolith 1 is thus advanced for example first of all to the metering head having the largest number of nozzles arranged in the same pattern as the zone 2 in case several more zones of this size have been determined the monolith is moved correspondingly and made to approach once again or repeatedly at varying locations the largest metering head thereafter for example the next smaller zones 3 of the monolith that have been determined are moved to the next smaller metering head until finally all those ducts 5 remain which require a separate treatment by a metering head having only one nozzle after this process has been performed the ducts 6 of the monolith 1 are sealed on one of its end faces the monolith is thereafter turned by 180 u00b0 and the process is carried out correspondingly but maintaining a complementary sealing pattern for the ducts after the controlled sealing of the ducts 6 on both end faces of the monolith 1 the latter is placed underneath a metering cylinder 28 filled with a ceramic material preferably the diameter of this cylinder corresponding approximately to the entire filter surface the metering cylinder 28 is connected via the conduit 29 to a metering facility 30 and is fed likewise with computer control with the ceramic composition present in the metering facility 30 by way of this cylinder a specific quantity of the ceramic mass is forced into the small ducts presently not as yet sealed with the first composition down to a certain desired depth subsequently.