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a body of certified astronomical instrument makers, with Lenoir among the first
seven appointed to the grade in 1788. He also established a new workshop at the
Observatory; the existing commercially-run workshops were too unskilled and
refused to make the unique astronomical instruments required by Cassini because
there was little chance of a repeat order that would help defray the considerable
capital sums necessary to set up the patterns and tools.
None of this progress could overcome the considerable class barrier between
astronomer and instrument maker in France. English instrument makers like James
Short and George Graham were scientists themselves, admitted to the Royal Society
and treated as equals by their compatriot scientists. The optician John Dolland was
even awarded the prestigious Copley Medal of the Royal Society. All of these
English instrument makers wrote scientific papers that were published in the jour-
nals of the Royal Society. By contrast, Cassini treated Lenoir as the semi-literate
worker that he was allowed to be, however experienced, ingenious and skilled he
was, even though Cassini also wrote with great respect to Jesse Ramsden, an English
instrument maker who made similar astronomical instruments to Lenoir.
The French instrument makers were on par with their English counterparts in
their professional skill but nowhere near their equal in social standing. It took the
events of 1792 to elevate their status when the Revolutionaries intervened in the elitist
attitudes of the Academy, ordered everyone to tutoyer 17 their colleagues and to place
the instrument makers on the decision-making committees. This change in status is
illustrated by the part that Lenoir played, equally with Borda, in developing the
repeating circle. Without his skill and contribution it would not have reached a practical
implementation. Borda sought in vain for a workman capable of making the instru-
ment with the required accuracy, especially the scale, until he discovered Lenoir.
Even then he initially planned to have Lenoir construct the instrument but not the
scales, intending to send them to England to be graduated. “In 1783 Borda asked M.
Lenoir to construct these circles for him with the reservation that he would have
them divided as he thought fit. The latter, stung by noble emulation, replied with
laudable pride that no one other than himself would graduate the instruments that he
had executed,” wrote Jumelin in a report to the government in 1792.
It was Lenoir who thought of using two telescopes, one for balance on either side
of the graduated circle and improved the mounting and thus the instrument's align-
ment and stability as well as the fineness of the adjustments that could be made to
align the telescopes on their target. He made many examples of various sizes for the
use of surveyors, hydrographers, navigators, and military engineers beyond the few
made for the meridian survey and astronomy - one belonging to the Museum of the
Conservatoire National des Arts et Métiers (National Academy of Arts and Sciences)
in Paris bears the serial number 350, so there must have been a lot of them made.
THE ACADEMY had concluded that it was worth measuring the Paris Meridian
again. It has to be said that there was a measure of self interest in the Academy's
17 The French language has two forms of the word “you”. The word vous is used both as a plural
and as a respectful form of address; the word tu is used to a friend and equal (or inferior). To use
the familiar form is called tutoyer .
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