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to fight for themselves and France besieged Barcelona, which fell in 1714, with
Catalonia and Valencia coming under the control of King Philip V. Franco-Austrian
hostilities were ended by the Treaty of Baden in 1714.
This was not a good ending for France, and the air of gloom at the finish of the
war was deepened by the death of Louis XIV and other members of his family in
1715. His funeral was, however, a cause for the poorer people to get drunk in cele-
bration because they had suffered so much from hunger in his lifetime. The end of
his reign, by which he had lost almost all that he had earlier gained, contrasted with
the optimism of his accession to the throne.
People
Gabriel-Philippe de la Hire (1677-1719)
Gabriel-Philippe de la Hire (Philippe II) was the son of the astronomer Philippe de la Hire and
was immersed in astronomy and mathematics from an early age, assisting his father in his
observations. In 1702, however, he was involved in a dispute with Jean Le Fèvre, editor of the
Connaissance de Temps
, who accused both father and son of plagiarism. Le Fèvre was expelled
from the Academy as a result of this incident. Although he did not produce anything innovative,
La Hire worked, like his father, on a wide range of problems in the arts and sciences.
Almost all of Louis XIV's legitimate children had died in childhood and the only
one to have a child died soon afterwards and predeceased the King. The succession
was passed from Louis XIV directly to his grandson who came to the throne as Louis
XV at the age of 5. His uncle, Philip II (Duc d'Orleans) was declared Regent. The
terms drawn up by Louis XIV before he died to effect all this attempted to restrict
the power of the Duc d'Orleans but eventually he took full control as Regent.
People
Nicholas Louis Lacaille (1713-1762)
Abbé Lacaille is best remembered for his expedition in 1750-53 to the Cape of Good Hope
where he measured the positions of the southern stars (nearly 10,000 of them, compared to
the previous best catalogue by Edmund Halley in 1677-78 of 350) and discovered over
forty nebulae and star clusters. He systematized and named fourteen southern constella-
tions, including some “modern” names which now seem quaintly historic, such as Antlia,
the Air Pump, Circinus, the Compasses, Fornax, the Chemical Furnace, Octans, the Octant,
and Pyxis, the Mariner's Compass.
Lacaille was born near Reims, the son of a
gendarme
and a member of an old and distin-
guished family. He developed an interest in mathematics and astronomy, and, self-taught,
took up an appointment at the Paris Observatory under Cassini in 1737. He was assigned to
help with the mapping of the Atlantic coast, where his work was so impressive he was chosen
to help Cassini on the meridian measurements in 1739. Lacaille took the most energetic,
leading role in the measurements measuring baselines at Bourges, Rodez and Arles and posi-
tions astronomically at Bourges, Rodez and Perpignan. Even in the severe winter weather of
1740/41 he surveyed across the mountains of the Auvergne and around Paris until the spring
of 1741, re-surveying Picard's baseline at Juvisy which he found to be 0.1% too long.
With this background one can certainly understand why Lacaille would have replicated a
geodesic survey in the Cape, where he measured the length over ¾ degree of latitude. He
was puzzled to find his results suggested the Earth was prolate (pointed at the poles) not
oblate (a flattened sphere). This seems to have been an error introduced into his measurements
by the gravitational deflection by Table Mountain of the plumb-bob used to determine the
vertical set-up of the instruments. Lacaille died at the comparatively early age of 49 of a
fever brought on by the rigors of his observing regimen.
None of the political turmoil, uncertainty of authority, diversion of taxes to fight the
wars, and the war-zone status of parts of the country was favorable to the
