Abstract: A nuclear magnetic resonance flowmeter comprising at least one coil (40) of electrically conductive material through which an electrical current flows when the apparatus is in use. This generates a magnetic field in a region through which flows a fluid the flow of which is to be measured and throughout which there is a uniform weak magnetic field such as the Earth's magnetic field. Electrical circuitry (46 to 52) is connected to the said at least one coil (40) to switch on and abruptly switch off such an electrical current. There is an NMR sensor (42) connected to the electrical circuitry (46 to 52) to provide a measure of the decay in the NMR signal from nuclei within such fluid following the abrupt switching off of such an electrical current. A processor (52) of the electrical circuitry (46 to 52) is formed and/or programmed to provide a measure of the flow of such fluid from the said measure of the decay. Also, a method of measuring the flow of a fluid using such a flowmeter.

Abstract: A portable water-driven rotary tool for drilling, grinding and polishing concrete and stone that provides for high torque and that uses water pressures as the power source, the tool including a water control valve, an impeller with blades and a drive shaft that has a longitudinal axial water passage disposed therethrough for diverting water used to power the tool onto a work surface for lubrication and as a cleaning agent.

Abstract: A portable water-driven rotary tool for drilling, grinding and polishing concrete and stone that provides for high torque and that uses water pressures as the power source, the tool including a water control valve, an impeller with blades and a drive shaft that has a longitudinal axial water passage disposed therethrough for diverting water used to power the tool onto a work surface for lubrication and as a cleaning agent.