Abstract: A chemical reaction is carried out by the wet method on a succession of samples. The chemical reaction is carried out within a reaction chamber which is connected to a fluid-conducting circuit. The reaction chamber is positioned within a microwave cavity. A predetermined quantity of sample is fed into the circuit upstream of the reaction chamber. At least one reactant is introduced into the circuit upstream of the reaction chamber. The reaction chamber, with the sample and reactant disposed therein, is heated by the application of microwaves for a predetermined time. The product of the reaction is recovered. The circuit is then rinsed with a rinsing liquid, and the steps are repeated on the remaining samples.