it was found, though it
still might be one of this class which had hitherto escaped detection. Or
it might be a "new star," one of those curious bodies which blaze up quite
suddenly to brightness and then die away gradually until they become
practically invisible. The most famous perhaps of these is the star which
appeared in 1572, and was so carefully observed by Tycho Brahe; but such
apparitions are rare, and altogether we have not records as yet of a score
altogether; so that in this latter case the discovery would be of much
greater interest than in the former. In either event it was desirable to
inform other observers as soon as possible of the existence of a strange
body; already some time had elapsed since the plate had been taken, March
16th, for the examination of which I have spoken was not made until March
24th. Accordingly, a telegram was at once despatched to the Central Office
at Kiel, which undertakes to distribute such information all over the
world, and a few post-cards were sent to observers close at hand who might
be able to observe the star the same night. Certain observations with the
spectroscope soon made it clear that the object was really a "new star."

[Sidenote: The discovery accidental.]

[Sidenote: Mrs. Fleming's discoveries.]

This, therefore, is the discovery which we made at Oxford: as you will
see, in an entirely accidental manner, during the course of a piece of
work in which it was certainly never contemplated. Its purely accidental
nature is sufficiently illustrated by the fact that if the plates
originally supplied by the makers had been of the proper quality, the
plate which led to the discovery would never have been taken. If the
plates exposed in February had been satisfactory, we should have been
content, and should not have repeated the exposure on March 16th. Again I
can testify personally how purely accidental it was that the examination
was made on March 24th to see whether anything could be saved, as I have
said, from the wreck. The idea came casually into my mind as I was walking
through the room and saw the neat pile of rejected plates; and one may
fairly call it an accidental impulse. This new star is not, however, the
first of such objects to have been discovered "accidentally"; many of the
others were found just as much by chance, though a notable exception must
be made of those discovered at the Harvard Observatory, which are the
result of a deliberate search for such