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EAB 462 EARTH the Eustachian tube and traversed by a chain of very small movable bones, ■which connect the membrane of the tympanum with the external ear. It lies, as its name implies, between the ex- ternal meatus and the labyrinth or in- ternal ear, and opens posteriorly into the cells contained in the mastoid por- tion of the temporal bone, and ante- riorly into the Eustachian tube. The cavity is of an irregular shape, and is lined by a very delicate ciliated epithe- lium, which is a prolongation of that of the pharynx through the Eustachian tube. Its external wall is in great part formed by the membrane of the tympa- num, which is nearly oval, and placed in a direction slanting inward, so as to form an angle of about 45° with the floor of the auditory canal. The Eustachian tube, into which the tympanic cavity opens anteriorly, is about an inch and a half in length, and passes dov^mward, forward, and into its opening in the pharynx. It is partly osseus but chiefly cartilaginous, and al- lows the free passage of air in and out of the tympanum. The internal ear or labyrinth is the essential part of the organ of hearing, being the portion to which the ultimate filaments of the auditory nerve are dis- tributed. It is composed of three parts: the vestibule, the semi-circular canals, and the cochlea, which form a series of cavities presenting a very complicated arrangement, and lying imbedded in the hardest part of the petrous portion of the temporal bone. They communicate externally with the tympanum through the fenestra ovalis, and the fenestra ro- tunda; and internally with the internal auditory canal, which conveys the audi- tory nerve from the cranial cavity to the internal ear. The very dense bone im- mediately bounding these cavities is termed the osseous labyrinth, to distin- guish it from the membranous labyrinth, which lies within a portion of it. The cochlea, so-called from its resemblance to a common snail-shell, consists of an osseous and gradually tapering canal, about an inch and a half in length, which makes two turns and a half spirally around a central axis, termed the modiolus, which is perforated at its base for the entrance of the filaments of the cochlear portion of the auditory nerve. This spiral canal gradually di- minishes toward the apex of the cochlea. At its base it presents an opening into the vestibule, partially divided into two. In the infant state, one of these open- ings (scala tympani) does not communi- cate with the vestibule, but is closed by the membrane of the fenestra rotunda. Its interior is sub-divided into two pas- sages (scalae) by an osseous lamina. This is the lamina spiralis, which incom- pletely divides the cochlea into an up- per passage, the scala vestibuli, and a lower one, the scala tympani — that is, the division is incomplete so far as the skeleton goes, but is completed during life by the lamina spiralis membranacea (or basilar membrane). EABL, a degree of the British nobility between marquis and viscount, the title of highest antiquity in England. The title was made hereditary by William the Conqueror, and for a time was used interchangeably with that of count, the corresponding title on the Continent. The wife of an earl is still called a countess. An earl's coronet is com- posed of eight pearls raised upon points, with small leaves between, above the rim. EARLE, MBS. ALICE MORSE, an American writer; born in Worcester, Mass., April 27, 1853. She has written extensively upon the manners and cus- toms of the colonial period in New Eng- land and New York. Among her numer- ous works are: "Curious Punishments of Bygone Days," Customs and Fash- ions in Old New England," "Colonial Dames and Goodwives," "Colonial Days in Old New York," "Sun Dials and Roses of Yesterday" (1902); "Two Cen- turies of Costume in America" (1903). She died in 1911. EARLHAM COLLEGE, an institution for higher education, founded under the auspices of the Orthodox Friends at Richmond, Ind., in 1859. The college is coeducational. There were in 1919 400 students and 25 instructors. Presi- dent, D. M. Edwards. EARLY, JURAL ANDERSON, an American military officer; born in Franklin co., Va., Nov. 3, 1816; gradu- ated at West Point, and served in the Florida and Mexican wars. During most of the years 1838-1861, however, he prac- ticed law in his native State. On the outbreak of the Civil War he entered the Confederate service as a colonel, and commanded a brigade at Bull Run, and a division at Fredericksburg and Gettys- burg. In 1864, after some successes, he was defeated by Sheridan in several bat- tles; and, Custer having also routed him at Waynesboro in March, 1865, he was relieved of his command a few days later. He subsequently returned to the practice of law. In 1867 he published "A Memoir of the Last Year of the War for Inde- pendence in the Confederate States." He died March 2, 1894. EARTH, the name applied to the third planet in order from the sun. To