Of minute precision.
No person will deny that the highest
degree of attainable accuracy is an object to be desired,
and it is generally found that the last advances towards
precision require a greater devotion of time, labour,
and expense, than those which precede them.
The first steps in the path of discovery, and the first
approximate measures, are those which add most to the
existing knowledge of mankind.
The extreme accuracy required in some
of our modern inquiries has, in some respects, had
an unfortunate influence, by favouring the opinion,
that no experiments are valuable, unless the measures
are most minute, and the accordance amongst them most
perfect. It may, perhaps, be of some use to show,
that even with large instruments, and most practised
observers, this is but rarely the case. The
following extract is taken from a representation made
by the present Astronomer-Royal, to the Council of
the Royal Society, on the advantages to be derived
from the employment of two mural circles:—
“That by observing, with two
instruments, the same objects at the same time, and
in the same manner, we should be able to estimate
how much of that occasional discordance from
the mean, which attends even the
most careful observations, ought to
be attributed to irregularity of refraction, and how
much to the IMPERFECTIONS of instruments.”
In confirmation of this may be adduced
the opinion of the late M. Delambre, which is the
more important, from the statement it contains relative
to the necessity of publishing all the observations
which have been made.
“Mais quelque soit le parti
que l’on prefere, il me semble qu’on
doit tout publier. Ces irregularites memes sont
des faits qu’il importe de connoitre.
LES SOINS les PLUS ATTENTIFS N’EN SAUROIENT
PRESERVER les OBSERVATEURS les PLUS EXERCES,
et celui qui ne produiroit que des angles toujours
parfaitment d’accord auroit ete singulierement
bien servi par les circonstances ou ne seroit pas
bien sincere.”—Base du Systeme
Metrique, Discours Preliminaire, p. 158.
This desire for extreme accuracy has
called away the attention of experimenters from points
of far greater importance, and it seems to have been
too much overlooked in the present day, that genius
marks its tract, not by the observation of quantities
inappreciable to any but the acutest senses, but by
placing Nature in such circumstances, that she is
forced to record her minutest variations on so magnified
a scale, that an observer, possessing ordinary faculties,
shall find them legibly written. He who can see
portions of matter beyond the ken of the rest of his
species, confers an obligation on them, by recording
what he sees; but their knowledge depends both on
his testimony and on his judgment. He who contrives
a method of rendering such atoms visible to ordinary
observers, communicates to mankind an instrument of
discovery, and stamps his own observations with a
character, alike independent of testimony or of judgment.