anet Ceres. This was the
first of the asteroids, so many more of which were to be revealed to
astronomical study during the next half-century. Father Piazzi's
discovery was made, not by accident, but as the result of detailed
astronomical work of the most painstaking character. He {171} had set
out to make a map of the heavens, and to determine and locate the
absolute position of all the visible stars. He had succeeded in
cataloguing over 7,000 stars when his attention was called to one,
hitherto supposed to be fixed, which he found had moved, during the
interval between two observations, from its original position. He made
still other observations, and thus determined the fact that it was a
planetoid and not a fixed star with which he had to deal. Needless to
say, his discovery proved a strong incentive to patient astronomical
study of the same kind; and it is to these, rather than to great
single discoveries, that we owe whatever progress in astronomy was
made during the nineteenth century.

Contemporary with both of these last-mentioned men, and worthy to
share in the scientific honors that were theirs, was the Abbe Hauey,
who toward the end of the second half of the eighteenth century
founded the science of crystallography; made a series of observations
the value of which can never be disputed, originated theories some of
which have served down to our own time as the basis of crystal
knowledge, and attracted the attention of many students to the new
science because of his charming personal character and his winning
teaching methods. His life is a typical example of the value of work
done in patient obscurity, founded on observation, and not on
brilliant theories; and what he accomplished stamps him as one of the
great {172} scientific geniuses of all time--one of the men who
widened the bounds of knowledge in directions hitherto considered
inaccessible to the ordinary methods of human investigation.

It is a commonplace of the lecturer on popular science at the present
day, that the impulse to the development of our modern scientific
discoveries which became so marked toward the end of the eighteenth
century, was due in a noteworthy degree to the work of the French
Encyclopedists. Their bringing together of all the details of
knowledge in a form in which it could be readily consulted, and in
which previous progress and the special lines of advance could be
realized, might be expected to prove a fruitful source of