MAUPERTUIS, PETER LOUIS MORCEAU DE, a
celebrated French academician, was born at St Malo
in 1698; and was there privately educated till he arriv-
ed at his 16th year, when he was placed under the ce-
lebrated professor of philosophy M. le Blond, in the
college of La Marche, at Paris. He soon discovered
a passion for mathematical studies, and particularly for
geometry. He likewise practised instrumental music
in his early years with great success, but fixed on no
profession till he was 20, when he entered into the ar-
my. He first served in the Grey musqueters; but in
the year 1720, his father purchased for him a company
of cavalry in the regiment of La Rocheguyon. He re-
mained but five years in the army, during which time
he pursued his mathematical studies with great vigour;
and it was soon remarked by M. Freret and other aca-
demicians, that nothing but geometry could satisfy
his active soul and unbounded thirst for knowledge.
In the year 1723, he was received into the Royal
Academy of Sciences, and read his first performance,
which was a memoir upon the construction and form
of musical instruments, November 15. 1724. During
the first years of his admission, he did not wholly con-
fine his attention to mathematics; he dpt into natu-
ral philosophy, and discovered great knowledge and
dexterity in observations and experiments upon animals.
If the custom of travelling into remote climates, like
the sages of antiquity, in order to be initiated into
the learned mysteries of those times had still subsisted,
no one would have conformed to it with greater eage-
ness than M. de Maupertuis. His first gratification
of this passion was to visit the country which had
given birth to Newton: and during his residence at
London he became as zealous an admirer and fol-
lower of that philosopher as any one of his own
countrymen. His next excursion was to Basil in
Switzerland, where he formed a friendship with the fa-
mous John Bernoulli and his family, which continued
to his death. At his return to Paris, he applied him-
self to his favourite studies with greater zeal than ever:
—And how well he fulfilled the duties of an academi-
cian, may be gathered by running over the memoirs of
the academy from the year 1724 to 1736; where it ap-
pears that he was neither idle nor occupied by objects
of small importance. The most sublime questions in
geometry and the relative sciences received from his
hands that elegance, clearness, and precision, so re-
markable in all his writings. In the year 1736, he
was sent by the king of France to the polar circle to
measure a degree, in order to ascertain the figure of
the earth, accompanied by Messrs Clairault, Camus,
Le Monnier, l'Abbe Outhier, and Celsius the cele-
brated professor of astronomy at Upsal. This distinc-
tion rendered him so famous, that at his return he was
admitted a member of almost every academy in Eu-
rope.
In the year 1740 Maupertuis had an invitation from
the king of Prussia to go to Berlin; which was too
flattering to be refused. His rank among men of let-
ters had not wholly effaced his love for his first pro-
fession, namely that of arms. He followed his Prus-
sian majesty into the field, and was a witness of the
dispositions and operations that preceded the battle of
Molwitz; but was deprived of the glory of being pre-
sent, when victory declared in favour of his royal pa-
tron, by a singular kind of adventure. His horse, dur-
ing the heat of the action, running away with him,
he fell into the hands of the enemy; and was at first
but roughly treated by the Austrian soldiers, to whom
he could not make himself known for want of lan-
guage; but being carried prisoner to Vienna, he re-
ceived such honours from their Imperial Majesties as
were never effaced from his memory. From Vienna
he returned to Berlin; but as the reform of the aca-
demy which the king of Prussia then meditated was
not yet mature, he went again to Paris, where his af-
fairs called him, and was chosen in 1742 director of
the Academy of Sciences. In 1753 he was received in-
to the French academy; which was the first instance
of the same person being a member of both the aca-
demies at Paris at the same time. M. de Maupertuis
again assumed the soldier at the siege of Fribourg, and
was pitched upon by Marshal Cogny and the Count
d'Argenson to carry the news to the French king of
the surrender of that citadel.
He returned to Berlin in the year 1744, when a
marriage was negotiated and brought about by the
good offices of the queen-mother, between our author
and Mademoiselle de Borck, a lady of great beauty and
merit, and nearly related to M. de Borck, at that time
minister of state. This determined him to settle at
Berlin, as he was extremely attached to his new spouse,
and regarded this alliance as the most fortunate cir-
cumstance of his life.
In the year 1746, M. de Maupertuis was declared
by his Prussian majesty president of the Royal Academy
of Sciences at Berlin, and soon after by the same prince
was honoured with the order of Merit: However, all
these accumulated honours and advantages, so far from
lessening his ardour for the sciences, seemed to furnish
new allurements to labour and application. Not a day
passed but he produced some new project or essay for
the advancement of knowledge. Nor did he confine
himself to mathematical studies only: metaphysics,
chemistry, botany, polite literature, all shared his at-
tention, and contributed to his fame. At the same
time, he had, it seems, a strange inquietude of spir-
it, with a morose temper, which rendered him
miserable amidst honours and pleasures.—Such a
temperament did not promise a very pacific life,
and he was engaged in several quarrels. He had
Maupertuis, a quarrel with Koenig the professor of philosophy at Franeker, and another more terrible with Voltaire. Maupertuis had inserted into the volume of Memoirs of the Academy of Berlin for 1746, a discourse upon the laws of motion; which Koenig was not content with attacking, but attributed to Leibnitz. Maupertuis, stung with the imputation of plagiarism, engaged the academy of Berlin to call upon him for his proof; which Koenig failing to produce, he was struck out of the academy, of which he was a member. Several pamphlets were the consequence of this; and Voltaire, for some reason or other, engaged against Maupertuis. We say, for some reason or other; because Maupertuis and Voltaire were apparently upon the most amicable terms; and the latter respected the former as his master in the mathematics. Voltaire, however, exerted all his wit and satire against him; and on the whole was so much transported beyond what was thought right, that he found it expedient in 1753 to quit the court of Prussia.
Our philosopher's constitution had long been considerably impaired by the great fatigues of various kinds in which his active mind had involved him; though from the amazing hardships he had undergone in his northern expedition, most of his future bodily sufferings may be traced. The intense sharpness of the air could only be supported by means of strong liquors, which served to increase his disorder, and bring on a spitting of blood, which began at least 12 years before he died. Yet still his mind seemed to enjoy the greatest vigour; for the best of his writings were produced, and most sublime ideas developed, during the time of his confinement by sickness, when he was unable to occupy his presiding chair at the academy. He took several journeys to St Malo, during the last years of his life, for the recovery of his health; And though he always received benefit by breathing his native air, yet still, upon his return to Berlin, his disorder likewise returned with greater violence.—His last journey into France was undertaken in the year 1757; when he was obliged, soon after his arrival there, to quit his favourite retreat at St Malo, on account of the danger, and confusion which that town was thrown into by the arrival of the English in its neighbourhood. From thence he went to Bourdeaux, hoping there to meet with a neutral ship to carry him to Hamburg, in his way back to Berlin; but being disappointed in that hope, he went to Thoulouse, where he remained seven months. He had then thoughts of going to Italy, in hopes a milder climate would restore him to health; but finding himself grow worse, he rather inclined towards Germany, and went to Neufchatel, where for three months he enjoyed the conversation of Lord Marischal, with whom he had formerly been much connected. At length he arrived at Basil, October 16. 1758, where he was received by his friend Bernoulli and his family with the utmost tenderness and affection. He at first found himself much better here than he had been at Neufchatel; but this amendment was of short duration; for as the winter approached, his disorder returned, accompanied by new and more alarming symptoms. He languished here many months during which he was attended by M. de la Condamine; and died in 1759.
He wrote in French, 1. The figure of the earth de-
termined. 2. The measure of a degree of the meridian. Maupertuis 3. A discourse on the parallax of the moon. 4. A dis- ||
course on the figure of the stars. 5. The elements of Maurice.
geography. 6. Nautical astronomy. 7. Elements of
astronomy. 8. A physical dissertation on a white inhabi-
tant of Africa. 9. An essay on cosmography. 10. Reflec-
tions on the origin of languages. 11. An essay on
moral philosophy. 12. A letter on the progress of the
sciences. 13. An essay on the formation of bodies.
14. An eulogium on M. de Montesquieu. 15. Letters,
and other works.