This beat theory of dissonance was first put forward by Joseph Sauveur (1653-1716) in 1700.
Robert Smith (Harmonics, 2nd ed., 1 759, p. 95) states that Sauveur " inferred that octaves and other simple concords, whose vibrations coincide very often, are agreeable and pleasant because their beats are too quick to be distinguished, be the pitch of the sounds ever so low; and on the contrary, that the more complex consonances whose vibrations coincide seldom are disagreeable because we can distinguish their slow beats; which displease the ear, says he, by reason of the inequality of the sound.
But Sauveur fixed the limiting number of beats for the discord far too low, and again he gave no account of dissonances such as the seventh, where the frequency of the beats between the fundamentals is far beyond the number which is unpleasant.
The cathedral of St Sauveur, which dates from the 11th, 12th and 13th centuries, is situated in this portion of Aix.
CHARLES FRANCOIS LEBRUN, duc de Plaisance (1739-1824), French statesman, was born at St-Sauveur-Lendelin (Manche) on the 19th of March 1739, and in 1762 made his first appearance as a lawyer at Paris.
Its chief building is the brick-built church of St Sauveur, which dates from the 13th century.
The former friend of Saint Just now offered his services to the Thermidorians, and after receiving from the Convention the title of "Sauveur de la Patrie," subdued the sans-culottes of Paris, when they rose in insurrection against the Convention on 12 Germinal (April 1).
Other interesting old churches are those of St Sauveur, St Michel de Vaucelles, St Jean, St Gilles, Notre-Dame de la Gloriette, St Etienne le Vieux and St Nicolas, the last two now secularized.
JULES AMEDEE BARBEY D'AUREVILLY (1808-1889), French man of letters, was born at Saint-Sauveur-le-Vicomte (Manche) on the 2nd of November 1808.