apparatus and instruments for the controlled feeding of material, be such material in liquid, gaseous or particulate (powders, flakes, granules, chips or pellets) form, including; metering pumps; pumps of all types in this class; flow rate controllers; volumetric and gravimetric controlled feeders and blenders for dry chemicals, pharmaceuticals, food products, plastics products; single and multi-auger feeders of all types in this class; automatic gas feed systems for chlorination and related processes; gas chlorination systems; chlorine residual analysers and controllers; chlorine leak detectors and alarms; chlorine flow recorders, evaporators, pressure reducing valves; chlorinators; sulphonators; ammoniators; on-line water quality monitors and controls; pool management systems; gladless pumps, including canned motor and magentic- drive centrifugal and rotary pups; single-stage high speed centrifugal pumps; compressors and blowers; chemical pumps, including horizontal and vertical singles and multi-state pumps; gear pumps; slurry pumps; diaphragm and tubular diaphragm pumps; submersible drainage effluent and sewage pumps; materials conditiong apparatus and instruments of all types in this class; and parts of and accessories for the aforesaid goods