Richard of Wallingford (1292–1336), abbot of St. Albans abbey, famously built a mechanical clock as an astronomical orrery about 1330.Great advances in accurate time-keeping were made by Galileo Galilei and especially Christiaan Huygens with the invention of pendulum-driven clocks along with the invention of the minute hand by Jost Burgi.The English word clock probably comes from the Middle Dutch word klocke which, in turn, derives from the medieval Latin word clocca, which ultimately derives from Celtic and is cognate with French, Latin, and German words that mean bell. The passage of the hours at sea was marked by bells and denoted the time (see ships bell). The hours were marked by bells in abbeys as well as at sea. Clocks can range from watches to more exotic varieties such as the Clock of the Long Now. They can be driven by a variety of means, including gravity, springs, and various forms of electrical power, and regulated by a variety of means such as a pendulum. Alarm clocks first appeared in ancient Greece around 250 BC with a water clock that would set off a whistle. This idea was later mechanized by Levi Hutchins and Seth E. Thomas.A chronometer is a portable timekeeper that meets certain precision standards. Initially, the term was used to refer to the marine chronometer, a timepiece used to determine longitude by means of celestial navigation, a precision firstly achieved by John Harrison.
Bandemia refers to an excess or increased levels of band cells (immature white blood cells) released by the bone marrow into the blood. It thus overlaps with the concept of left shift—bandemia is a principal type of left shift and many (perhaps most) clinical mentions of the latter refer to instances of this type.It is a signifier of infection (or sepsis) or inflammation. Measurement of it can play a role in the approach to appendicitis. See also
Granulocytosis

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