SIEYES. 149 SIGHT. measures he succeeded in closing the celebrated Jacobin Club. Perceiving that a dictator was needed in France, lie became anxious to secure the cooperation of some powerful military leader, and on the return of Bonaparte from Egj'pt he entered into a league with him, the re- sult of which was the Revolution of the ISth Brumaire (November 9, 1799) and tlie institution of the provisional Consulate, Siey6s, Napoleon, and Roger Ducos being the first three consuls. Sieyfs and Napoleon dilTered irreconcilably as to tile distribution of power, but the former had to give way, and finally retired from the Gov- ernment. As a reward for his services he re- ceived on his retirement a sum of 600,000 francs, the estate of Crosne, and a seat in the Senate. The title of Count of the Empire was conferred upon him. Banished at the second Restoration as a regicide, he went to Brussels, and did not return to France till after the Revolution of 1S30. when he was elected a member of the Academy. He died in Paris. His Rcconnais- saiico et ij.rpositioii des droits de I'hommc et du citoxjen (Paris, 1789) undoubtedly led up to the famous Declaration of the Riglits of Man. His famous constitution is found explained in Boulay, "Theorie constitutionelle de Sieyfes," from the mcnioires incdits of Sieyfes (Paris, 18.36). Con-' suit also Mignet, Etude sur .S'lci/i's (Paris. ls:l(i). SIGEBEKT (sig'c-bert) OF GEMBLOURS, zhiiN'bloor' (c.1030-1112). A Flemish chron- icler, born in Brabant. He worked under Abbot Obert in the cloister of Gemblours, from which he went to study under Saint Vincent at Metz, and then returned to CJemblours. His principal work is Chronicon, a chronicle of the world to 1111. Consult Hirsch, De Vita et t^criptis Sige- herti (Berlin, 1841). SIGEL, s?'gd, Fr. z (1824-1902). A German- American soldier, born at Sinsheim, in Baden. In 1S4S he took a prominent part in the revolu- tionary movement in Baden, and on the renewed outbreak of the insurrection, in the spring of 1840, commanded the troops on the Neekar. In IMay he was made a memlier of the provisional government and Minister of War; later he be- came Mieroslawski's adjutant-general, and after that general's retirement, in July, Sigel led the remainder of the revolutionary army, which re- treated into Switzerland. In 18.52 he emi- grated to the United States; and in 18.58 he went to Saint Louis, where he taught in a German military institute, and edited a mili- tary periodical. On the outbreak of the Civil War he espoused the side of the North, and or- ganized a regiment of infantry and a battery of artillery, which rendered good service in the oc- cupation of Camp Jackson. On July 5, 1861, he was defeated in the battle of Carthage; later he took part in the battle of Dug Springs ; and after the death of General Lyon at Wilson's Creek, conducted the retreat of the army. He was made a brigadier-general of vol- unteers, and at the battle of Pea Ridge. !March 8, 1862. he ordered a well-timed charge which de- cided the day. Soon afterwards he was made a major-general of volunteers, and was placed in command of Harper's Ferry. He commanded the First Corps in the campaign which terminated with the second battle of Bull Run, August, 1862, and in February, 1864, was given com- mand of the Department of West Virginia. He soon afterwards led an expedition into the Shenandoah Valley, but on May 15th was de- feated at New Jlarket by a superior force under General Breckenridge. In consequence he was relieved of his command by Cieneral Hunter, and was put in charge of the division guarding Harper's Ferry. In the following July, he suc- cessfully defended ilaryland Heights again.st General Early, but the Administration had lost confidence in him, and he was relieved of com- mand. He resigned from the army in May, I8l).5. and was for a short time editor of the Baltimore Weckei: From 1871 until 1874 he was register of New York City, and from 1886 until ISSO was United States pension agent at the same place. He also lectured, engaged in the advertising business, and for several years published the New York Monthly, a German- American periodical. SIGHT (AS. ge-sih>, OHG. ge-sUit, Ger. Ge- sicht, from AS. scon, OHG. sehan, Ger. sehen. to see; connected with Lat. se</»i, Gk. Ireadat, hepes- thai, Lith. sekti, Skt. sac, to follow), Defects of. L'nder this head we shall consider certain af- fections of the eyesight due to some known or unknown peculiarity of the optical apparatus (including the optic nerve) — viz. near-sighted- ness, far-sightedness, double vision, color-blind- ness, night-blindness, and day-blindness. Defects due to errors of refraction include the first two of these. Xear-sightedness, short-sightedness, or myopia is often popularly confounded with dim or weak sight; but in reality short sight applies exclusively to the range and not to the poirer of sight, and a short-sighted person may possess the acutest power of vision for near objects. In this afl'ection, the rays which ought to come to a focus upon the retina converge to a point more or less in front of it. The cause of this defect prob- ably differs in different persons. It nearly al- ways arises from elongation of the globe in its antero-posterior diameter, more rarely from in- creased curvature of the cornea, increase in re- fractive power of the lens in the early stage of senile cataract, or from an imperfect power of the eye to adjust itself to objects at various dis- tances. The distance at which objects arc per- ceived most distinctly by the perfectly normal eye ranges from 16 to 20 inches: an eye which cannot perceive objects distinctly beyond 10 inches may fairly be regarded as short-sighted; and in extreme cases the point of distinct vision may be 3, 2, or even only I inch from the eye. There is frequently an hereditary ten- dency to near-sightedness, but it is rarely con- genital. It is often acquired by excessive use of the eyes at an early age for reading or other near work. Overstudy under unfavor- able circumstances and poor health favor its development. As a general rule the inhabi- tants of towns are much more liable to it than persons living in the country, and students and literary men are the most liable of all. The fre- quency of this affection in the cultivated ranks points directly to its principal cause — tension of the eyes for near objects. Prolongation of the visual axis is attributed to ( 1 ) pressure of the muscles on the eyeball in strong convergence of the visual axis; (2) increased pressure of the fluids resulting from accumulation of blood in
