h a uniformity of longitude, and when we look for the reasons
which have caused those attempts (many of which were very happily
conceived) to fail, we are struck with the fact that it appears due to
two principal causes--one of a scientific and the other of a moral
nature. The scientific cause was the incapacity of the ancients to
determine exactly the relative positions of different points on the
globe, especially if it was a question of an island far from a
continent, and which consequently could not be connected with that
continent by itinerary measurements. For example, the first meridian
of Marinus of Tyre and Ptolemy, placed on the Fortunate Isles, in
spite of its being so well chosen at the western extremity of the then
known world, could not continue to be used on account of the
uncertainty of the point of departure. That much to be regretted
obstacle caused the method to be changed. It became necessary to fall
back on the continent. But then, in place of a single common origin of
longitude indicated by nature, the first meridians were fixed at
capitals of countries, at remarkable places, at observatories. The
second cause to which I just now alluded, the cause of a moral
nature--national pride--has led to the multiplication of geographical
starting-points where the nature of things would have required, on the
contrary, their reduction to a single one.

In the seventeenth century, Cardinal Richelieu, in view of this
confusion, desired to take up again the conception of Marinus of Tyre,
and assembled at Paris French and foreign men of science, and the
famous meridian of the Island of Ferro was the result of their
discussions.

Here, gentlemen, we find a lesson which should not be lost sight of.
This meridian of Ferro, which at first had the purely geographical and
neutral character which could alone establish and maintain it as an
international first meridian, was deprived of its original
characteristic by the geographer Delisle, who, to simplify the
figures, placed it at 20 degrees in round numbers west of Paris. This
unfortunate simplification abandoned entirely the principle of
impersonality. It was no longer then an independent meridian; it was
the meridian of Paris disguised. The consequences were soon felt. The
meridian of Ferro, which has subsequently been considered as a purely
French meridian, aroused national susceptibilities, and thus lost the
future which was certainly in store for it if it had rema