Abstract: This invention relates to a pneumatic conveying system for pulverulent and particulate materials and provides a system adapted to operate at a high frequency of despatch with low material velocities and relatively low pressures and low volumes of air in relation to the material, the system being characterized in that a material despatch vessel has an automatic non-return outlet valve, a fill valve, an arrangement for venting air which enables the rapid filling of the vessel, a pneumatic system to ensure a firm closure of the despatch vessel's fill valve, a pneumatic system to regulate the despatch of material in accordance with the pressures obtaining in the conveying pipe line.