GREENWICH OBSERYATORY. 
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observers. Let us now pass in review the works that have been 
actually accomplished thereby in furtherance of the objects for 
which the Observatory was constituted. We begin with the 
formation of star catalogues, for these are the foundations of 
exact astronomy. Flamsteed formed a catalogue of 3,310 stars, 
that remained the standard work of its kind for half a century, 
and has, in respect of selection and nomenclature of the stars it 
comprised, served as the basis of every catalogue since pro- 
duced. Halley did nothing in this department. Bradley 
worked wonders ; he laid the foundations of the present fabric 
Fig. 4. 
of mensurative astronomy. In 1750, when his new instruments 
were mounted, he began the daily course of meridional observa- 
tions of principal stars, sun, moon, and planets which has con- 
tinued without interruption (save by bad weather) to the pre- 
sent time. His star observations were incorporated into a 
catalogue (which comprised 3,222 stars) by Bessel, and, with 
values of the constants of refraction, aberration, precession, and 
other elements deduced therefrom, was brought forth by the 
illustrious Konigsberg astronomer in a great work, whose title 
expresses its character — we allude to the “ Fundamenta Astro- 
nomise.” The rich harvest that Bradley reaped has not yet 
