The general procedure is based upon a determination of volume of water in the vessel. The described procedures are applicable to ware with capacities in the range of 0,1 to 2000 ml. These include transfer and one-mark pipettes without subdivision, graduated measuring pipettes and dilution pipettes, burettes and volumetric flasks. The apparatus, materials, accuracy, setting of the meniscus, delivery time and test procedure and handling of the different types of vessels are specified.