MEMOIR OF DELAMBRE. 131 
ten years. With entire unanimity of suffrages the prize was assigned to the 
author of the base of the metrical system. 
The length of a determinate part of the meridian was at last known with ex- 
traordinary precision, and upon this result, together with that of the memorable 
experiments of Lefevre-Gineau, has been founded the established system of 
French measures. 
‘This great work comprehends all the experiments which have been made in 
different places on the length of the pendulum. conformably to the processes 
invented by Borda; as well as all the observations made with the design of 
prolonging the are of the meridian to Fromentera, and also towards the north, 
where it unites the geodesic labors of France with those of Great Britain. 
One of the most remarkable results of modern science is that which relates 
to the elliptical form of the terrestrial globe. The flattening of the regions 
around the poles, as determined by the revolution of the globe upon its axis, is 
demonstrated by all our geodesic measurements, as it is also by a comparison 
of the lengths of the pendulum; and, what must be regarded as one of the most 
astonishing attestations to the perfection of our astronomic theories, the measure 
of this ellipticity is deducible with great exactness from an attentive observa- 
tion of the movements of the moon. In the course of that planet, irregularities. 
have been discovered which are owing to the action of the earth, and which 
could not exist if the earth were an exact sphere. Even the amount of the 
flattening has been deduced from these irregularities with more precision than: 
was attainable by immediate measurements carried on successively in different. 
regions of the globe, 
In this we see a striking proof of the progress of science, for not a century 
has elapsed since the elliptical figure of the earth was still a problem. Not 
only was the depression of the polar region disputed within the walls of acade- 
mies, but a theory directly the contrary of this had been proposed and obsti- 
nately maintained. In our day all doubts are resoived. Geodesic operations 
in France, England, Equatorial America, and the British possessions in India; 
a comparison of the length of the seconds pendulum as observed in different 
climates; and, as already remarked, the theory of the lunar inequalities—all 
concur in giving the same value as the measure of terrestrial ellipticity. But 
this question of the figure of the earth, so prolific of important results, can never 
be discussed without reference to that great system of operations for which we 
are mainly indebted to Delambre. Already an associate of most foreign acade- 
mies, and member of the bureau of longitudes in France, he was elected by the 
Institute perpetual secretary for the class of mathematical sciences. 
We must now advert to the happy union which he contracted with a party 
every way worthy of him, the mother of a youth named De Pommard, who had: 
accompanied him in all his geodesic expeditions. Under the tuition of this 
mother, the young man had acquired, in addition to correct principles of literary 
taste, a familiar acquaintance with the finest productions of foreign literature.. 
Delambre attached himself more and more to this companion of his labors,. 
developed his talents, and enlightened him by his counsels and example. The 
mother appreciated justly the value of such a friendship, and it is not difficult 
to imagine how much her heart was touched by the advantages which resulted 
from it. Having become a widow, Madame de Pommard espoused the friend. 
and protector of her son—the man whose talents and character were honored 
by the whole of scientifie Europe. She honored them herself, for no one could. 
better appreciate high endowments of the heart and intellect. The motives 
which brought about this union rendered it fortunate ; but the family thus ten- 
derly united was not destined to a durable happiness. It was smitten by the 
unexpected and deplorable loss of the son, who had been the object of so many 
vows, anxieties, and hopes. His mother found at least as much consolation as: 
the calamity admitted of in the tender affection of Delambre. Thus eighteen 
