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had all its good grain thrashed out, for at this moment several 
German astronomers are engaged in a re-reduction of his 
observations, believing that they can get from them even more 
than Bessel obtained. Maskelyne did not aim at producing a 
great catalogue ; he confined himself to thirty-six of the prin- 
cipal stars, whose places he sought to fix with the utmost pos- 
sible exactness, in order that they might serve as reference- 
points of the first order. Pond accumulated a long series of 
observations, and produced a catalogue of 1,112 stars, which 
was the most valuable contribution to the sidereal astronomy of 
the time, and is second in accuracy to no modern catalogue. 
The present Astronomer Royal has already produced four large 
catalogues ; the first from the observations during the twelve 
years 1836-47 ; the second from the six years 1848-53 ; the 
third from the seven years 1854-60, and the fourth from the 
seven years 1861-67. The numbers of stars in. these cata- 
logues average over 2,000 each ; each contains all the funda- 
mentals, and together they include the greater portion if not 
all the stars visible at Greenwich down to the fifth magnitude, 
and the majority of the sixth. They are sought all the world 
over, wherever accurate astronomy is pursued for its own sake or 
for geographical or geodetical purposes, and they have served 
and will serve again as the best materials for researches upon 
the proper motion of the stars or of the solar system. 
Then as to the moon ; Greenwich has alone sufficiently sup- 
plied the investigators of her movements from the time of 
Newton to the present. At so critical a period was the 
Observatory established that Flamsteed actually fed Newton, 
so to speak, from hand to mouth with places of the moon for 
perfecting the lunar theory which the latter was then deducing 
from his theory of universal gravitation ; and there is an entry 
in Flamsteed’s note-book of the author of the “ Principia ” 
coming down to Greenwich one Sunday evening for twelve 
observations of the moon of which he was in urgent need. 
Halley, though he did no star work, made some moon observa- 
tions, and compared them with his own lunar tables ; it was 
the only good piece of regular work that he did. He was the 
exception we previously spoke of to the consentaneous character 
of the Royal Astronomers ; and his case shows that a man may 
be a great astronomer, and yet fail in the office of Royal 
Observator, which requires the exercise of no small amount of 
self-denial. The lunar observations of Bradley, Maskelyne, and 
Pond, have to be spoken of connectedly, for they were reduced 
en masse by the present Astronomer Royal, and they form the 
basis of the Lunar Tables that are now in almost universal use. 
But before this stupendous uniform reduction, the Greenwich 
Observatory had furnished 1,200 moon observations to improve 
