By September the star was as much as thirty-nine seconds
more to the north than it had been in March, then it returned towards
the south, regaining in December the same situation which it had
occupied twelve months before.
This movement of the star being directly opposite to the movements
which would have been the consequence of parallax, seemed to show
that even if the star had any parallax its effects upon the apparent
place were entirely masked by a much larger motion of a totally
different description. Various attempts were made to account for the
phenomenon, but they were not successful. Bradley accordingly
determined to investigate the whole subject in a more thorough
manner. One of his objects was to try whether the same movements
which he had observed in one star were in any similar degree
possessed by other stars. For this purpose he set up a new
instrument at Wanstead, and there he commenced a most diligent
scrutiny of the apparent places of several stars which passed at
different distances from the zenith. He found in the course of this
research that other stars exhibited movements of a similar
description to those which had already proved so perplexing. For a
long time the cause of these apparent movements seemed a mystery.
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