In technology, the development and use of precise measuring, analysis, and control equipment. Among the oldest known instruments of measurement was the armillary sphere, an astronomical instrument used in ancient China and Greece. The compass was a striking advance in navigational instrumentation made about the 11th century. Theodolites made accurate determination of locations possible in the 18th century. Instrumentation developed rapidly in the Industrial Revolution. Manufacturing required precision instruments, such as the screw micrometer, which could measure 0.0001 in. (0.0025 mm). The industrial application of electricity required instruments to measure current, voltage, and resistance. Today most manufacturing processes rely on instrumentation for monitoring chemical, physical, and environmental properties. Instruments used in medicine and biomedical research are just as varied as those in industry. See also analysis.