DESICCANT COMPOSITIONS CONTAINING AS A DESICCANT CONCENTRATED SULFURIC ACID OR PHOSPHORUS PENTOXIDE, IN ADMIXTURE WITH A SOLID CARRIER AND A DYESTUFF WHICH EXHIBITS A DIFFERENT COLOR IN THE PRESENCE OF HYDRATED DESICCANT, E.G., 1-HYDROXY-4-(2-SULFO - 4,6 - DINITROPHENYLAZO)-NAPHTHALENE WHEN SULFURIC ACID IS EMPLOYED AS DESICCANT AND NEUTRAL RED WHEN PHOSPHORUS PENTOXIDE IS EMPLOYED.