George Ticknor was an American literary historian. He was born in 1791 at Boston, Massachusetts and died in 1871. Educated at Dartmouth, in 1815 he went to Europe where he visited most of the capitals and studied at Gottingen. From 1819 until 1835 he was professor of Belles-Lettres and of French and Spanish at Harvard. The following three years he spent in Europe, and in 1849 he published his magnum opus, The History of Spanish Literature. Further visits to Europe followed, and in 1864 he brought out his Life of Prescott. His later years were devoted to the Boston Public Library which he helped to establish in 1852, and was one of the trustees from 1852 until 1866, and was president of the Boston Library in 1965. On his death, Thomas Tickell bequeathed his collection of books to the Boston Public Library. Research George Ticknor
Jakob Boehme was a German mystical writer. He was born in 1575 and died in 1624. He was apprenticed to a shoemaker in his fourteenth year, and ten years later he was settled at Gorlitz as a master-tradesman, and married to the daughter of a thriving butcher of the town. He was much persecuted by the religious authorities, and at his death the rites of the church were but grudgingly administered to him. Raised by contemplation above his circumstances, a strong sense of the spiritual, particularly of the mysterious, was constantly present with him, and he saw in all the workings of nature upon his mind a revelation of God, and even imagined himself favoured by divine inspirations. His first work appeared in 1616, and was called Aurora. It contains his revelations on God, man, and nature. Among his other works are De tribus Principiis, De Signatura Herum, Mysterium Magnum, etc. His writings all aim at religious edification, but his philosophy is very obscure and often fantastic. The first collection of his works was made in Holland in 1675 by Henry Betke; a more complete one in 1682 by Gichtel (published in ten volumes in Amsterdam). William Law published an English translation of them, in two volumes. A sect, taking their name from Jakob Boehme, was formed in England. Research Jakob Boehme
Albert Popwell was an American actor. He was born in 1926 at New York and died in 1999 following surgery. He starred in the first four Dirty Harry movies with Clint Eastwood, playing four different characters in each. He was the bank robber in Dirty Harry, a pimp in Magnum Force, a black militant leader in The Enforcer, and Harry's partner in Sudden Impact. Research Albert Popwell
The basilar part of the occipital bone is that part which forms the floor of the cranial cavity, housing the brain. The basilar part meets the vomer and sphenoid bone in the anterior, and the temporal bones at the sides. The most apparent characteristic of the basilar part of the occipital bone is the large foramen magnum, a round opening in the bone which allows the spinal cord to pass through the skull. Research Basilar Part
The brain is the primary component of the nervous system, occupying the cranial cavity. Without its outermost protective membrane, the dura mater, the brain weighs an average of 1.4 kilograms, comprising about 97% of the entirecentral nervous system. The brain is connected to the upper end of the spinal cord (which connects through the foramen magnum of the skull) and is responsible for issuing nerve impulses, processing nerve impulse data, and engaging in the higher order thought processes. The brain is divided into three parts: the large cerebrum, the smaller cerebellum, and the brainstem leading to the spinal cord. The brainstem is also descriptively divided into the medulla oblongata, the midbrain, and the pons. The right hemisphere of the brain is a part of the cerebrum. The cerebrum, or forebrain, forms the bulk of the brain, formed of a large mass of white and grey neural fiber in the upper cranium. It is responsible for the higher thought processes (memory, judgement, reason), processing sensory data, and with initiating willful motor processes, such as voluntary muscle flexion. The cerebrum is composed of two lateral halves, or hemispheres, which feature a number of folds (gyri) and furrows (sulci) and which are connected in the middle at the medulla. Containing about a trillion neurons, the human brain is the most complex mechanism known, and its many functions are still largely a mystery. Research Brain
The medulla oblongata is the lowest part of the brainstem and serves as the site of connection between the brain and the spinal cord. Located just above the foramen magnum in the skull and in front of the cerebellum, the
medulla oblongata contains a number of nerve centers which are responsible for controlling involuntary processes such as the heartbeat, breathing, and body temperature regulation. It is only about 2.5 centimeters wide and comprises less than one percent of the weight of the central nervous system. In spite of its small size, though, it is integral in the transmission of nerve impulses between the spinal cord and the higher brain. Many of the nerve fibres which pass through the medulla oblongata cross over, so that many impulses from the right side of the brain control functions on the left side of the body and vice-versa. Research Medulla Oblongata
The occipital bone forms the back of the skull and the cranial base. It is joined to the two parietal bones and to the mastoid processes of the temporal bones on the side by the lambdoid suture. At the base of the occipital bone, at the basilar parts, the
occipital bone is attached to the sphenoid bone. The occipital bone features a significant bump, or external occipital protuberance, in the center of the back of the skull, while the Nuchal line defines the cusp at which the occipital bone curves under to the base. The large opening, or foramen magnum, in the
occipital bone can be seen in the inferior view of the skull, and allows the nerves of the upper spinal cord to pass through the skull between the brain and the rest of the spinal cord. Research Occipital Bone
The rectus capitis anterior (rectus capitis anticus minor) is a deep back muscle that helps flex the head. It originates from the transverse process of the atlas and inserts in the occipital bone near the foramen magnum. It is innervated by the first and second cervical nerves and is supplied by the muscular branches of the aorta. Research Rectus Capitis Anterior
The skull is one of the principle groups of bones in the human anatomy. The skull consists of twenty-six bones: eight bones form the skull, which houses the brain and ear ossicles, plus fourteen facial bones, which form the front of the face, jaw, nose, orbits, and the roof of the mouth, three more bones make up the inner ear ossicles, and one more, the hyoid bone, is in the neck and is attached to the temporal bone by ligaments and anchors the tongue. The skull also contains a dental arcade of teeth, which are technically not bones, though they do share some of the compositional characteristics of bonetissue. Children may grow twenty deciduousteeth, which will eventually fall out and be replaced by the permanent teeth.
The bones of the skull include the frontal bone, the occipital bone, two parietal bones, and two temporal bones. The lower rearmost part of each temporal bone is called the mastoid process, but because it is separated from the temporal bone, proper, by a suture, it is often considered a separate bone. The sphenoid bone forms the central base of the skull and spans the skull from side to side, the greater wings forming side plates of the skull. The sections of the ethmoid bone are positioned between the orbits, forming the walls and roof of the nasal cavity, while the three middle ear ossicles (stapes, malleus, and incus) are located within the temporal bones on each side of the skull. The U-shaped hyoid bone is found in the neck, and is attached by ligaments to the temporal bones. In the face, the two maxillary bones form much of the orbits, nose, upper jaw and roof of the mouth, while the zygomatic bones form the cheeks. The lachrymal bones are located on the inner sides of the orbits and are attached to the ethmoid bone and maxillary bones. Within the nasal cavity, the vomer is located in the low center and forms the thin flat bone of the nasalseptum, while two inferior urbinates form the lower sides of the cavity and two palate bones form the floor of the nasal cavity as well as the roof of the mouth.
The mandible is the only movable part of the skull, forming the lower jaw and mounting the teeth. The bones of the skull, with the exception of the mandible, are held together by very thin sutures, or seams, in which the periosteum of the individual bones interweave with each other, and are cemented by a fibrous, connective tissue. In the newborn, these sutures are not yet developed, with the bones being attached by cartilage which ossifies over time as the bones of the skull fuse together. The most evident external sutures of the skull include the coronal suture, joining the frontal bone and parietal bone, the sagittal suture, joining the parietal bones to each other, the lambdoid suture, joining the occipital and parietal bones, the squamous suture, joining the temporal and sphenoid bones to the parietal bone on each side of the skull.
The pterion is the short segment of the suture joining the squamous and parietal bones. The bones of the skull also feature a number of sinuses and foramina. Four pairs of sinuses flank the nasal cavity. Two are found in the maxillary bone, and are called maxillary sinuses. The sphenoid bone forms two paranasal sinuses called the sphenoids, and the ethmoid bone forms the two paranasal sinuses called ethmoids. Additionally, the frontal sinuses are located in the frontal bone just behind the roof of each orbit. The foramen magnum is a large, round opening in the base of the skull which admits the spinal cord, while at the base of each temporal bone is the external auditory meatus, which serve as the auditory canals. Just above each orbit in the frontal bone is a small notch or hole, called a supraorbital foramen, and just below each orbit, in the maxillary bone, is an infraorbital foramen. Two more openings, one on each side of the skull, can be found in the frontal processes of the zygomatic bones, and are called zygomatofacial foramina.
On each side of the mandible, just below the lower canines, are the mental foramina. These facial foramina serve to admit blood vessels and nerves through and into the bone. The teeth are mounted in the maxillary bone and the mandible, and are brought together for chewing by the hinge-like motion of the mandible. An average adult will have thirty-two teeth, evenly arrayed on the maxilla and mandible. Research Skull
The spinal cord is one of the primary portions of the central nervous system, serving as a medium for signals to be sent from the brain to the structures of the body, and received from them in return. Extending from the medulla oblongata, through the foramen magnum in the base of the skull, to the base of the vertebral column, the spinal cord is about half of a centimeter in diameter, and is slightly flattened. The spinal cord itself passes through the vertebral canal created by the vertebral arches, and sends out roots and branches. These structures contain bundles of nerve fibres which extend all the way down the body, innervating even the skin of the tips of the toes. The spinal cord features both efferent and afferent nerve pathways, so that nerves may be transmitted to the body's structures as well as received from them.
Paired sets of nerves branch out from the spinal cord along the vertebral column, with the lowest of these forming the sacral plexus of nerves. The sympathetic nerves travel alongside the spinal cord in the sympathetic nerve trunk, which features periodic clusters of nerves, called ganglia, which deal with specific organ groups. The spinal cord floats in a spinal fluid which protects and nourishes it and, as with the brain, is covered by a meningeal membrane composed of three layers: the pia mater, the arachnoid, and the dura mater. Damage to the spinal cord results in inability to transmit and receive nerve impulses to and from the specific area supplied by the damaged section of the spinal cord, and all sections below it, resulting in paralysis and numbness. Inflammation of the spinal covering is a condition called spinal meningitis. Research Spinal Cord
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Abbreviations
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