Semois (also spelt Semoy and SemoyS), a river of less than 120 m. in length rising near Arlon in Belgium, and flowing into the Meuse near Montherme in France. It is Belgian for about loo m. and French for the remainder, entering France a short distance west of the village of Bohan. It passes through the most picturesque scenery in Belgium and is remarkable for its sinuous course, its length of 120 m. representing only 47 in a straight line. Bouillon is the only town on its banks, and since it is not navigable it has escaped the contamination of manufacturing life; its valley remains an ideal specimen of sylvan scenery and medieval tranquillity.
[[Semonville, Charles Louis Huguet, Marquis De]] (1759-1839), French diplomat, was born in Paris on the 9th of March 1759, the son of one of the royal secretaries. Minister and envoy extraordinary of France at Genoa in 1790-1791, he was instructed by Dumouriez to go to Turin to detach Victor Amadeo III. of Sardinia from the Austrian alliance, but was not permitted to cross the Sardinian frontier. In 1793 he had started with H. B. Maret (afterwards duc de Bassano) for Italy where they had missions to Florence and Naples respectively, when the two envoys were kidnapped by Austrian orders in the Valtelline. They remained in a Tirolese prison until December 1795, when there was an exchange of prisoners on the release of Madame Royale, daughter of Louis XVI., from the Temple. In 1799 Bonaparte, through whose influence his release had been obtained, sent him to the Hague to consolidate the alliance between France and the Batavian Republic. In this mission he was entirely successful, and he is credited with another diplomatic success in the inception of the Austrian marriage. He accepted the Restoration and sat on the commission which drew up the charter. Semonville, who enjoyed a great measure of Louis XVIII.'s confidence, took no part in the Hundred Days. A frank opponent of the extremist policy of Charles X., he tried to save him in 1830; in company with Antoine d'Argout he visited the Tuileries and persuaded the king to withdraw the ordinances and to summon the Council. He had been made a count of the Empire in 1808, and marquis in 1819. He died in Paris on the 11th of August 1839.
