The watch; its construction, its merits and defects, how to choose it, and how to use it (1860)
Piaget, Henry F · New York, Printed by C. Vinten for the author · leaf 21
Lever, or Anchor Escapement. A-duplex watch is so called because it receives itsimpulse from a double wheel. 12 … Duplex Escapement, A chronometer watch is that which has the vibra-tion of the balance free, or detached from the influenceof the maintaining power, except at receiving its impulse and unlocking.
Clocks and watches
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
