Page:The American Cyclopædia (1879) Volume XI.djvu/129

 MANOMETER MANSABT 121 lumns, the combined height of mercury sup- ported in column will be 100 inches, or about 6-66 atmospheres. The compressed-air mano- FIG. 2. Multiple-Branch Manometer. meter, fig. 8, is constructed upon the assump- tion that the confined air in the gauge expands and is condensed in accordance with Boyle's law. A is a U-shaped glass tube, one end of which communicates with the steam cham- ber, while the other end is closed. It has its flexure stopped with mercury, and a scale is attached, which is graduated by connecting the apparatus with an open-air manometer. It will be seen that as the mercury in A rises, the pressure is doubled for every reduction of the confined air to one half its volume, so that as the column approaches the top the grad- uated spaces must be nearer together. The metallic-spring manometer may be constructed FIG. 3. Compressed-air Manometer. FIG. 4. Bourdon's Pressure Gauge. by having a piston press against a spiral spring, which is also connected with an index ; or a flat copper tube (elliptic section), bent in a spi- ral, may be connected at one end with the steam chamber, and at the other with an in- dex, as in Burden's pressure gauge, shown in fig. 4. Increased pressure causes the spiral to uncoil, by which the index is moved over the graduated arc. M KKSA, a town of Spain, in 'the province and 30 m. N. X. W. of the city of Barcelona, near the left bank of the Llobregat river ; pop. about 15,000. It is one of the most picturesque towns in Catalonia and the centre of a rich farming district, and has extensive manufac- tures of broadcloth, cotton, silk, tape, ribbons, gunpowder, and brandy. The streets are clean and well paved, but many of them are crooked and steep, and lined with quaint old-fashioned houses. There are some elegant churches and other public buildings, and in the neighbor- hood is the famous monastery of Montserrat, and the " cave of St. Ignatius," where Loyola passed some time in retirement before found- ing the society of Jesus. Manresa was taken by the French under Macdonald, March 30, 1811, when more than 800 buildings were burned, including hospitals and churches. This wan- ton act so incensed the Catalans, that they fell upon the rear of the French army on its march to Barcelona, and destroyed 1,000 men. MANS, Le, a town of France, capital of the department of Sarthe, 118 m. S. W. of Paris, on the "W. bank of the river Sarthe, here crossed by three bridges; pop. in 1872, 46,981. It is the seat of a bishop, consists of an old town and a new town, has a considerable trade in local products, and manufactures coarse woollens, yarns, lace, linen, paper, and soap. The cathedral of St. Julien, dating from the 12th century, is famous for its fine Gothic choir and painted windows. It is a place of great antiquity, having been founded in the 2d century by the Romans, and called Suindinum or Cenomani, after the Gallic peo- ple of the same name, in whose territory it was situated. During the war of the league Le Mans was captured by Henry IV. ; and in De- cember, 1793, it was the scene of the destruc- tion of the Vendean army, when more than 10,000 persons were slaughtered. On Jan. 11 and 12, 1871, the French army of the Loire, under Gen. Chanzy, was here defeated and almost annihilated by Prince Frederick Charles of Prussia. The town itself was occupied by the Germans on Jan. 12. MMSART, or Mansard. I. Francois, a French architect, born in Paris in 1598, died there in 1666. At the age of 22 he distinguished him- self by the restoration of the hotel Toulon. In 1624 he attracted the attention of Cardi- nal Richelieu, who commissioned him to erect the church of the Feuillants in the rue St. Ho- nore, and he was subsequently employed in many other great works in Paris and in the provinces. Among the numerous chateaux erected from his plans are those of Berny, Blgrancourt, Choisy, Gevres, Fresnes, and Mai- sons. He built the facade of the church of the