Page:The American Cyclopædia (1879) Volume XV.djvu/83

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SKATE ing place to what is almost a complete shoe, while one of the favorite skates is made wholly of iron or steel, without straps, and fastened to the boot by metal clamps. Motion on skates is very rapid. It is said that the Frieslanders will go for a long time at the rate of 15 m. an hour, and for short distances this rate has been greatly exceeded. "Parlor" skates, hav- ing in place of runners rollers of wood, metal, papier mach6, or India rubber, arranged in a line, or like the wheels of a carriage, are used on floors and pavements. With these skates experts can execute the ordinary curves, and even many intricate figures. SKATE, a fish. See KAY. SKEAT, Walter William, an English philologist, born in London, Nov. 21, 1835. He gradu- ated at Christ's college, Cambridge, in 1858, became a fellow there in 1860, mathematical lecturer in 1864, and afterward English lec- turer. In 1873 he helped to found the English dialect society, and he has edited most of its publications. Besides continuing for the Cam- bridge press the Anglo-Saxon Gospels begun by J. M. Kemble, and editing several publica- tions for the Oxford press, the philological society, and the early English text society, he has published " The Songs and Ballads of Uhland," translated from the German (1864) ; "A Tale of Ludlow Castle" (1866) ; "A Mceso- Gothic Glossary " (1868) ; " Hand List of some Cognate Words in English, Latin, and Greek " (1871) ; " Questions for Examination in English Literature" (1873) ; " The Gospels of St. Mark and St. Luke, in Anglo-Saxon and Northum- berland Versions synoptically arranged, with Collations exhibiting all the Readings of all the Manuscripts" (2 vols., 1875); and "Plutarch- Shakespeare," biographies (vol. i., 1875). SKELETON (Gr., a dried body, from GK&- Av, to desiccate), the bony and cartilaginous framework of animals, and the ligneous struc- ture of the leaves of plants. In the higher animals the skeleton is internal (endo-skele- ton) ; in many of the lower it is external (exo- skeleton). When the bones are joined by nat- ural ligaments, they form a natural skeleton; when they are joined by wires and straps, the skeleton is said to be artificial. The study of the skeletons of different animals belongs to the subject of comparative anatomy; the human skeleton only will be described here. Bones may be classified as long, round, flat, and short. (See BONE.) The human skeleton consists of 208 bones, exclusive of the teeth, which are in reality parts of the digestive apparatus, and are developed from the mucous membrane. For convenience the skeleton may be divided into four regions : 1, the skull ; 2, the trunk ; 8, the upper extremities; 4, the lower extrem- ities. The skull contains 30 bones, in three divisions, cranium, ears, and face. There are 8 cranial bones, viz. : 1 frontal, 2 parietal, 2 temporal, 1 occipital, 1 sphenoid, and 1 eth- moid. The frontal bone forms the forehead, upper part of the eye sockets, and front part SKELETON 75 of the floor of the cranial cavity. Just above the inner angles of. the eyebrows are two marked prominences called the superciliary ridges, at which points the two tables *of the bone separate considerably, enclosing cavities called the frontal sinuses which communicate with the nasal passages. The parietal bones, occupying the upper part and sides of the skull, are separated from each other by the sagittal suture, and from the frontal bone by the coro- nal suture. A curved ridge traverses both frontal and parietal bones at each side, which marks the origin of the fibres of the temporal muscle, lying in a depression behind and below the ridge, called the temporal fossae. The temporal bones, situated at the sides and base of the skull, consist each of three portions : an upright or squamous portion, a posterior or mastoid portion, and an internal or petrous portion. The upright portion articulates with the parietal bone by the squamous suture. The mastoid portion has a projection, felt behind the ear, called the mastoid process, which has a cellular structure, communicating with the middle ear or tympanum; the cells are not developed till after puberty. The petrous (hard, stony) portion is in the form of a trian- gular pyramid, and lies upon one of its sides in the base of the skull, its apex pointing for- ward and inward. One of the openings into it, the internal auditory canal, transmits the audi- tory and facial nerves, and it also contains the tympanum. The temporal bones are pierced ex- ternally by the external auditory canal, which transmits the sonorous pulsations to the mem- brane of the tympanum. The under surface of the bone articulates with the lower jaw bone to form the joint. Just in front of this, and a little above, a process called the zygo- matic springs forward to meet another of the same name from the cheek bone, forming a horizontal arch, the zygomatic, under which the tendon of the temporal muscle passes. The occipital bone consists of an upright and a basilar portion ; the latter contains a large orifice, the foramen magnum, through which the brain connects with the spinal cord. On each side of the foramen magnum there is a condyle having an articular surface which rests upon a corresponding condyle of the atlas, the upper bone of the vertebral column. The ba- silar portion articulates in front with the body of the sphenoid bone, fig. 4, which in turn articulates with the ethmoid, fig. 5, the latter being situated at the root of the nose and held in position by the frontal and several bones of the face. There are 8 ear bones, 4 in each ear, situated in the tympanum ; they are described in the article EAR. The 14 bones of the face are 2 nasal, 2 upper jaw or superior maxillary, 2 lachrymal, 2 cheek or malar bones, 2 palate bones, 2 inferior turbinated (in the nose), 1 vomer (septum of the nose), and 1 lower jaw, or inferior maxillary bone. (See illustrations.) Each upper jaw bone contains a large cavity called the maxillary antrum, which communi-