. If an experimentalist make a mistake, his only course
to win the confidence of his fellow-labourers in science, and to render
his future observations of any use, is to acknowledge it in the most
full and explicit manner. The very qualifications which contribute to
the professional excellence of the soldier, constitute his defects when
he enters the paths of science; and it is only in those rare cases where
the force of genius is able to control and surmount these habits,
that his admission to the offices of science can be attended with any
advantage to it.

Another objection deserving notice, although not applying exclusively to
the military profession, is, that persons not imbued with the feelings
of men of science, when they have published their observations, are too
apt to view every criticism upon them as a personal question, and
to consider that it is as offensive to doubt the accuracy of their
observations as it is to doubt their word. Nothing can be more injurious
to science than that such an opinion should be tolerated. The most
unreserved criticism is necessary for truth; and those suspicions
respecting his own accuracy, which every philosophical experimenter will
entertain concerning his own researches, ought never to be considered as
a reproach, when they are kept in view in examining the experiments of
others. The minute circumstances and apparently trivial causes which
lend their influence towards error, even in persons of the most candid
judgment, are amongst the most curious phenomena of the human mind.

The importance of affording every aid to enable others to try the merits
of observations, has been so well expressed by Mayer, that I shall
conclude these remarks with an extract from the Preface to his
Observations:

"Officii enim cujusque observatoris ease reor, de habitu instrumenti
sui, de cura ac precautione, qua usus est, ad illud recte tractandum,
deque mediis in errores ejus inquirendi rationem reddere publice, ut
aliis quoque copia sit judicandi, quanta fides habenda conclusionibus ex
nostris observationibus deductis aut deducendis. Hoc cum minus fecissent
precedentis saeculi astronomi, praxin nimis secure, nimisque theoretice
tractantes, factum inde potissimum est, ut illorum observationes tot
vigiliis tantoque labore comparatae tam cito obsoleverint." P. viii.

There are certain duties which the Royal Society owes to its own
character as well as to the public, which, having been on some oc