Clock chronometer

Zeit-lose, /. colchicum. -mass, n. measure of time (Music) time, rhythm (Gram.) quantity. -massstab, m. time scale, -messer, m. chronometer, time piece, watch, clock, -messung, /. time measurement timing, -puukt, m. point of time, moment, zeitraubend, p.a, time-consuming. 

Because radioactive decay is a nuclear process, the rate of radioactive decay is totally unaffected by any external factors. Unlike chemical reactions, therefore, there is no dependency on temperature, or pressure, or any of the other environmental factors which affect the rate at which normal chemical reactions occur. This is the reason why radioactive decay chronometers, such as 14C, Ar-Ar, and U-series methods, are so important in geology and archaeology - they provide an absolute clock . 

A chronometer is a very precise clock or watch and, if constructed so that it can be started or stopped (for precise timing) at will, it is known as a stopclock or stopwatch. 

Many standard lab activities use simple measuring devices such as a thermometer, a clock (or wristwatch, chronometer or stopwatch), a ruler (or micrometer or tape measure), or an electrical meter (e.g. voltmeter, ammeter). Humidity is measured with a hygrometer. 

A unique answer to this question is not possible since an "age" is a time interval between two events and an age may depend on the specific chronometer used. An accurate chronometer must involve a mechanism operating on a predictable, but not necessarily constant rate. The "clock" starts by an event beginning the time interval and its end must be clearly and sharply recorded. Chronometers used in modem geo- and cosmo-chronology usually involve long-lived, naturally occurring radioactive isotopes such as the U-isotopes, Rb or... 

The manufacture of primitive stone tools and fire required a qualitative appreciation for the most common measures of mass, time, number, and length. The concept of time has been appreciated for millennia. In comparative terms it is qualified by longer and shorter, sooner and later, more or less. Quantitatively, it has been measured in seconds, hours, days, lunar months, and years. Calendars have existed for well over 6000 yr and clocks—instruments to measure time intervals of less than a day—were common as long as 6000 yr ago. Chronometers are devices that have higher accuracy and laboratory models have a precision of 0.01 s. 

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