Page:The American Cyclopædia (1879) Volume II.djvu/706

 686 BLACKWELL'S ISLAND BLADDER BLACKWELL'S ISLAND, the site of several of the charitable and penal institutions of the city of New York. It lies in the East river, opposite the city from 50th to 84th street, is If m. long and m. wide, and is included in the 19th ward. (See NEW YORK.) BLAKWOOD, William, a Scottish bookseller and publisher, born in Edinburgh, Nov. 20, 1776, died Sept. 16, 1834. He was apprenticed to a bookseller, and conducted business succes- sively in Glasgow and London till 1804, when he established himself in Edinburgh as a dealer in old books. In 1817 he commenced the pub- lication of " Blackwood's Edinburgh Magazine," of which he was the conductor, although he availed himself of the advice and assistance of Wilson, Lockhart, and others. The magazine soon acquired popularity, and became the ac- knowledged organ of the tory party in Great Britain. " Blackwood " has contained contri- butions from many of the foremost writers of its day; and several novels of acknowledged merit first appeared in its pages, including " The Caxtons," " My Novel," and " What Will he Do with it ? " by Bulwer. The " Noctes Ambrosianse," mainly written by Wilson, ex- tending to 71 numbers, was begun in 1822, and continued with occasional intermissions till 1835. The house founded by William Black- wood is one of the leading publishing firms in Great Britain, and its principal place of busi- ness has for some years been in London. BLADDER, a musculo-membranous bag, cyst, or pouch, which serves as a reservoir for the urine secreted in the kidneys. It is called ve- sica urinwria, to distinguish it from the gall bladder, a small cyst connected with the liver and the biliary ducts as a reservoir for bile. The bladder is situated in the pelvis, immedi- ately behind the sympJiysis pulis, and in front of the rectum or terminal portion of the intes- tines in the male in front of the uterus and vagina in the female. Thus placed in the low- est portion of the trunk in front, it communi- cates by means of two long tubes called ure- ters with the two kidneys, placed high up in the back, just above the lumbar region, on each side of the vertebral column. It communicates with the exterior by means of a single tube called the urethra, through which the urine is voided. In infancy it is of a pyriform shape, and situated almost entirely in the abdomen ; it undergoes a change of form in the adult, and sinks deeper in the pelvic cavity. It then as- sumes the shape of a short oval, compressed in its anterior and posterior walls ; its lower sur- face expands on the rectum, and forms what is termed by anatomists the bas-fond of the blad- der. In the female its transverse diameter is greater than it is in the male, owing to the po- sition of the uterus and vagina between the bladder and the rectum. It increases in dimen- sions with advancing age, and is larger in fe- males than in males, probably from habitual distention, arising from constraint. The direc- tion of the bladder is oblique, being inclined forward and upward. It is retained in its po- sition by ligaments. Anatomists have divided it into six regions or surfaces, for the facility of description and surgical operation; these are named anterior, posterior, superior, inferi- or, and left and right lateral. The anterior surface lies behind the symphysis pubis, with which it is connected by loose connective tissue. When distended, the bladder rises, and its an- terior surface comes in contact with the recti muscles of the abdomen. The posterior surface is covered by the peritoneum, which is reflect- ed upon it from the rectum in the male, and from the uterus and vagina in the female. The lateral and superior regions are partially cov- ered by the peritoneum. The inferior region, or bas-fond, is the most important in a surgical point of view. It is bounded before by the prostate gland, and behind by the peritoneum. Attached to it in the male we find the veawulce seminalet and the vasa deferentia, which con- verge to the prostate gland, leaving a triangular space, where the bladder is only separated from the rectum by a quantity of fatty connective tissue surrounding numerous small vessels, chiefly veins. In the female this region rests on the vagina, which separates it from the rec- tum. The anterior and inferior regions of the bladder being left uncovered by folds of the peritoneum, the surgeon is able to perform op- erations on those parts without injuring that membrane, which is so liable to dangerous in- flammation from wounds. The walls of the bladder are composed of three layers or coats, united' by connective tissue: an internal or mucous membrane, a middle or muscular coat, and an external or serous coat, formed by folds of the peritoneum. The muscular coat is com- posed of pale fibres interlacing in all directions, and enabling the bladder to contract so per- fectly as to expel every drop of its contents. The neck of the bladder differs in structure from the rest of the organ, being composed of a somewhat fibrous whitish substance, and form- ing a connecting medium between the bladder and the urethra. Its posterior part rests upon the rectum ; its anterior is surrounded below and at the sides by the prostate gland, which is peculiar to the male. This gland is com- posed of an aggregation of mucous follicles, forming three lobes, one on each side of the neck of the bladder, and one below, communi- cating by means of small ducts with the ure thra. The inner coat or lining of the bladder, being a portion of the genito-urinary mucous membrane, not only lines the bladder, but is prolonged upward through the ureters into the kidneys, and downward along the urethra. It is of a pale rose color, with a smooth surface when the bladder is distended, and corrugated when empty. This membrane secretes a viscid fluid termed mucus, which protects it from the acrimony of the urine with which it would otherwise be in contact. The secretion of the urine is performed by the kidneys, which are constantly active, without any apparent