suggestive
investigation. As a matter of fact, however, a detailed knowledge of
the past in science often seems to be rather a hindrance than a help
to original genius, always prone to take its own way if not too much
disturbed by the conventional knowledge already gained. Most of the
great discoverers in science were comparatively young men when they
began their careers as original investigators; and it was apparently
their freedom from the incubus of too copious information that left
their minds untrammelled to follow their own bent in seeking for
causes where others had failed to find any hints of possible
developments.

This was certainly the case with regard to many of those distinguished
founders who lived in centuries prior to the nineteenth. Most of {173}
them were men under thirty years of age, and not one of them had been
noted, before he began his own researches, for the extent of his
knowledge in the particular department of science in which his work
was to prove so fruitful. Their lives illustrate the essential
difference there is between theory and observation in science. The
theorizer reaches conclusions that are popular as a rule in his own
generation, and receives the honor due to a progressive scientist; the
observer usually has his announcements of what he has actually seen
scouted by those who are engaged in the same studies, and it is only
succeeding generations who appreciate how much he really accomplished.

This was especially exemplified in the case of the Abbe Hauey, whose
work in crystallography was to mean so much. What he learned was not
from books, but from contact with the actual objects of his department
of science; and it is because the example of a life like this can
scarcely fail to serve a good purpose for the twentieth-century
student, in impressing the lesson of the value of observation as
opposed to theory, that its details are retold.

Rene Just Hauey was born 28 February, 1743, in the little village of
Saint-Just, in the Department of Oise, somewhat north of the center of
France. Like many another great genius, he was the son of very poor
parents. His father was a struggling linen-weaver, who was able to
support himself only with difficulty. At first {174} there seemed to
be no other prospect for his eldest son than to succeed to his
father's business. Certainly there seemed to be no possibility that he
should be able to gain his livelihood by any other means than by the
work