British optician who invented
a number of precision instruments used in astronomy, geodesy, and navigation.
Throughout most of his life, he worked for the family firm of mathematical
instrument makers, assuming full control after the retirement in 1819
of his uncle Peter Dollond. His micrometer made of rock crystal, announced
in 1821, was used by the English astronomer William Rutter Dawes in measuring
close double stars. Other inventions followed, including improvements
to astronomical and navigation devices. Dollond received the council medal
of the Great Exhibition of 1851 for his atmospheric recorder that simultaneously
measured and recorded on paper tape temperature, atmospheric pressure,
wind speed and direction, evaporation, and electrical phenomena. |