Page:The American Cyclopædia (1879) Volume III.djvu/192

 186 BRAILLE BRAIN left bank of the Danube, 103 m. N. E. of Bu- charest; pop. about 16,000. It is the chief port of Wallachia. The trade consists in the produce of the country, such as barley, wheat, maize, linseed, hides, tallow, timber, and to- bacco. It is chiefly conducted by Greeks ; but many English and other merchants are engaged in it. Braila suffered much by the Turkish wars in the 18th century, and was burned by the Russians in 1770. Afterward it was re- stored to the Turks, but surrendered to Russia in 1828. Since the subsequent treaty of peace of Adrianople, it has continued to form part of Wallachia. BRAILLE, Louis, the inventor of a method of writing with points for the blind, born at Lagny, a suburb of Paris, in 1809, died in 1852. He lost his sight at the age of six years by an accident, and in 1819 was admitted to the in- stitute for the blind at Paris. He devoted him- self to the study of the piano, violoncello, and organ, and became one of the most distinguish- ed organists of Paris. In 1827 he was appoint- ed a professor in the royal institute, and soon after modified M. Charles Barbier's system of writing with points so as to render it practica- ble and convenient. This system was intro- duced into most of the continental schools for the blind. Braille also applied his system to musical notation. BRAIN, a collective term, denoting those parts of the nervous system (excluding the nerves) which are contained in the cranial cavity, viz. : the brain, in its popular signification, or the cerebral hemispheres ; the cerebellum, or little brain ; and the medulla oblongata, or the up- per part of the spinal cord. Each of these has its special part to play in the animal organism. The brain alone, of the animal tissues, is direct- ly influenced by the mental acts of living be- ings, and through it are effected the mutual reactions of mind and body ; the phenomena of sensation and volition, and the mysterious agency of intellect and instinct, are all manifest- ed through the channels of the nervous centres, the most important of which is the brain. The peculiar substance through which all these ac- tions take place exists in two forms, the vesicu- lar and the fibrous. The vesicular nervous mat- ter is gray or ash-colored, granular in texture, containing nucleated nerve vesicles, largely sup- plied with blood, and is the originator of ner- vous power ; it is sometimes called the " cortical substance," from its forming a thin layer over the exterior of the brain ; it is also found in the centre of the spinal cord. The fibrous nervous matter is generally white, firm, and inelastic, composed of tubular fibres ; it is less vascular than the other, and constitutes nearly the whole of the nerves and the greater part of the spinal cord ; it simply propagates the impressions sent to or from the vesicular matter. The two kinds do not occur together except in the ner- vous centres. In the vertebrated animals, ner- vous matter is a soft and delicate substance, owing the greater part of its tenacity to the vascular and fibrous tissues connected with it. The chemical composition of nervous matter lias been well ascertained by Fourcroy, Vau- quelin, and Fr6my ; but the distinguishing characters of the gray and white substance are as yet imperfectly known. Fourcroy notices the great amount of water in the cerebral matter, from six eighths to seven eighths of its weight, upon which its softness is in great part depen- dent. According to Vauquelin's analysis in 1812, the brain is an emulsive mixture of albu- men, fatty matter, and water holding in solu- tion saline and other matter common to it with other tissues. The following table gives the result of his analysis : Albumen ...................................... 7-00 Phosphorus ..................................... 1'50 Osmazome ...................................... 1 '12 Acids, salts, sulphur ............................. 6-15 Water... ................... 80-00 100-00 The medulla oblongata contains more cerebral fat, but less albumen, osmazome, and water. Fremy's analysis, published in the Annales de Chimie, 1841, confirmed that of Vauquelin, and showed the following proportions : 7 part* of albumen, 5 of fatty matter, and 80 of water. He extracted from the fatty matter the follow- ing secondary principles: 1, cerebric acid, a white granular, crystalline substance, contain- ing no sulphur, a little phosphorus, and 66 per cent, of carbon; 2, oleophosphoric acid, sepa- rated from the cerebric by its solubility in ether, containing about 2 per cent, of phosphorus in the condition of phosphoric acid, and combined with elaine ; 3, cholesterine, the same as that obtained from bile (brains preserved in alcohol are apt to be surrounded by a crystalline sub- stance resembling cholesterine) ; 4, traces of elaine, margarine, and fatty acids. The brain is remarkable for containing phosphorus, which varies m quantity at different periods of life, being the least in infancy and old age ; the maximum of water is found in infancy, an in- teresting fact in connection with the serous effusions so prevalent at this period of life ; it has been ascertained that the idiot brain con- tains less phosphorus than the normal organ, this being diminished from nearly 2 to less than 1 per cent., indicating possibly an important hint for the treatment of diseases accompanied by deterioration of the mental powers. The microscopic elements of nervous tissue are fibres and cells. The fibrous nervous matter, or white central substance, contains tubular fibres or nerve tubes, and the gelatinous fibres found chiefly in the sympathetic system. The white fibres are membranous cylinders, of a pearly lustre, consisting of an external delicate, trans- parent sheath, within which is a layer of thick, fluid, highly refractive matter, called the " med- ullary layer; " while the central portion is oc- cupied by a finely granular mass, termed the " axis cylinder." The medullary layer, how-
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