Johann Georg Repsold - Encyclopedia

REPSOLD, JOHANN GEORG (1771-1830), German instrument maker, was born at Wremen in Hanover on the 23rd of September 1771, and became an engineer and afterwards chief of the fire brigade in Hamburg, where he started business as an instrument maker early in the 19th century. He was killed by the fall of a wall during a fire at Hamburg on the 14th of January 1830. The business was continued by his sons Georg (1804-1884) it as layer of cubical cells, which are continuous near the anterior border with the cells of the peritoneum. Deep to these is the ovarian stroma, composed of fibrous tissue, and embedded in it are numerous nests of epithelial cells, the Graafian follicles, in various stages of development. During the childbearing period of life some of these will be nearing the ripe condition, and if one such be looked at it will be seen to contain one large cell, the ovum, surrounded by a mass of small cells forming the discus proligerus. At one point this is continuous with a layer of cells called the stratum granulosum which lines the outer wall of the follicle, but elsewhere the two layers are separated by fluid, the liquor folliculi. When the follicle bursts, as it does in time, the ovum escapes on to the surface of the ovary.

The Fallopian tubes receive the ova and carry them to the uterus. That end of each which lies in front of the ovary is called the fimbriated extremity, and has a number of fringes (fimbriae) hanging from it; one of the largest of these is the ovarian fimbria and is attached to the upper or tubal pole of the ovary. The small opening among the fimbriae by which the tube communicates with the peritoneal cavity is known as the ostium abdominale, and from this the lumen of the tube runs from four to four and a half inches, until it opens into the cavity of the uterus by an extremely small opening. In the accompanying figure (fig. 6) the Fallopian tube and ovary Parovarium Ligament Fallopian tube I Ovary of ovary Hydatid Fimbriated end of tube Round ligament Broad ligament are pulled out from the uterus; this, as has been explained, is not the position of the ovary in the living body, nor is it of the tube, the outer half of which lies folded on the front and inner surface of the ovary. The Fallopian tubes, like many other tubes in the body, are made chiefly of unstriped muscle, the outer layer of which is longitudinal and the inner circular; deep to this are the submucous and mucous coats, the latter being lined with ciliated epithelium '(see' Epithelial Tissues), and thrown into longitudinal pleats. Superficially the tube is covered by a serous coat of peritoneum. The calibre gradually contracts from the peritoneal to the uterine opening.

The uterus or womb is a pear-shaped, very thick-walled, muscular bag, lying in the pelvis between the bladder and rectum. In the non-pregnant condition it is about three inches long and two in its broadest part, which is above. The upper half or body of the uterus is somewhat triangular with its base upward, and has an anterior surface which is moderately flat, and a posterior convex. The lower half is the neck or cervix and is cylindrical; it projects into the anterior wall of the vagina, into the cavity of which it opens by the os uteri externum. This opening in a uterus which has never been pregnant is a narrow transverse slit, rarely a circular aperture, but in those uteri in which pregnancy has occurred the slit is much wider and its lips are thickened and gaping and often scarred. The interior of the body of the uterus shows a comparatively small triangular cavity (see fig. 6, B), the anterior and posterior walls of which are in contact. The base of the triangle is upward, and at each lateral angle one of the Fallopian tubes opens. The apex leads into the canal of the cervix, but between the two there is a slight constriction known as the os uteri internum. The canal of the cervix is about an inch long, and is spindle-shaped when looked at from in front; its anterior and posterior walls are in contact, and its lining mucous membrane is raised into a pattern which, from its likeness to a cypress twig, is called the arbor vitae. This arrangement is obliterated after the first pregnancy. On making a mesial vertical section of the uterus the cavity is seen as a mere slit which is bent about its middle to form an angle the opening of which is forward. A normal uterus is therefore bent forward on itself, or anteflexed. In addition to this, its long axis forms a marked angle with that of the vagina, so that the whole uterus is bent forward or anteverted. As a rule, in adults the uterus is more or less on one side of the mesial plane of the body. From each side of the uterus the peritoneum is reflected outward, as a two-layered sheet, to the side wall of the pelvis; this is the broad ligament, and between its layers lie several structures of importance. Above, there is the Fallopian tube, already described; below and in front is the round ligament; behind, the ovary projects backward, and just above this, when the broad ligament is stretched out as in fig. 6, are the epoophoron and parodphoron with the duct of Gartner.

The round ligament is a cord of unstriped muscle which runs from the lateral angle of its own side of the uterus forward to the internal abdominal ring, and so through the inguinal canal to the upper part of the labium majus.

The epoophoron or parovarium is a collection of short tubes which radiate from the upper border of the ovary when the broad ligament is pulled out as in fig. 6. It is best seen in very young Vaginal cavity B children and represents the vasa effer entia in the male. Near the ovary the tubes are closed, but nearer the Fal lopian tube they open into another tube which is nearly at right angles to them, and which runs toward the uterus, though in the human subject is generally lost before reaching that organ. It is known the duct of Gartner, and. is the homologue of the male epididymis and vas deferens. Some of the outermost tubules of the ep06phoron are sometimes distended to form hydatids. Nearer the uterus than the ep08phoron a few scattered tubules are occasionally found which are looked upon as the homologue of the organ of Giraldbs in the male, and are known as the paroophoron. The vagina is a dilatable muscular passage, lined with mucous membrane, which leads from the uterus to the external generative organs; its direction is, from the uterus, downward and forward, and its anterior and posterior walls are in contact, so that in a horizontal section it appears as a transverse slit. As the orifice is neared the slit becomes H-shaped. Owing to the fact that the neck of the uterus enters the vagina from in front, the anterior wall of that tube is only about 21 in., while the posterior is 31. The mucous membrane is raised into a series of transverse folds or rugae, and between it and the muscular wall are plexuses of veins forming erectile tissue. The relation of the vagina to the peritoneum is noticed under Coelum and Serous Membranes.

Uterus

a

Lateral angle of uterus

The vulva or pudendum comprises all the female external generative organs, and consists of the mons Veneris, labia majora and minora, clitoris, urethral orifice, hymen, bulbs of the vestibule, and glands of Bartholin. The mons Veneris i° the A A. F. Dixon, Cunningham's Text-Book of Anatomy. FIG. 6. - A. The Uterus and Broad Ligament seen from behind (the broad ligament has been spread out). a, b and c, the isthmus tubae, the ligament of the ovary, and the round ligament of the right side cut short. B. Diagrammatic Representation of the Uterine Cavity opened up from in front.

Cavity of body Cavity of cervix elevation in front of the pubic bones caused by a mass of fibrofatty tissue; the skin over it is covered by hair in the adult. The labia majora are two folds of skin, also containing fibro-fatty tissue and covered on their outer surfaces by hair, running down from the mons Veneris to within an inch of the anus and touching one another by their internal surfaces. They are the homologues of the scrotum in the male. The labia minora are two folds of skin containing no fat, which are usually hidden by the labia majora and above enclose the clitoris, they are of a pinkish colour and look like mucous membrane.

The clitoris is the representative of the penis, and consists of two corpora cavernosa which posteriorly diverge to form the crura clitoridis, and are attached to the ischium; the organ is about an inch and a half long, and ends anteriorly in a rudimentary glans which is covered by the junction of the labia minora; this junction forms the prepuce of the clitoris.

The orifice of the urethra is about an inch below the glans clitoridis and is slightly puckered.

The hymen is a fold of mucous membrane which surrounds the orifice of the vagina and is usually only seen in the virgin. As has been pointed out above, it is represented in the male by the fold at the opening of the uterus masculinus. Occasionally the hymen is imperforate and then gives rise to trouble in menstruation.

The bulbs of the vestibule are two masses of erectile tissue situated one on each side of the vaginal orifice: above they are continued up to the clitoris; they represent the bulb and the corpus spongiosum of the male, split into two, and the fact that they are so divided accounts for the urethra failing to be enclosed in the clitoris as it is in the penis.

The glands of Bartholin are two oval bodies about half an inch long, lying on each side of the vagina close to its opening; they represent Cowper's glands in the male, and their ducts open by minute orifices between the hymen and the labia minora.

From the above description it will be seen that all the parts of the male external genital organs are represented in the female, though usually in a less developed condition, and that, owing to the orifice of the vagina, they retain their original bi-lateral form.

For further details see Quain's Anatomy (London: Longmans, Green & Co.); Gray's Anatomy (London: Longmans, Green & Co.); Cunningham's Text-Book of Anatomy (Edinburgh: Young J. Pentland), or Macalister's Anatomy (London: Griffin & Co.).

Embryology. The development of the reproductive organs is so closely interwoven with that of the urinary that some reference from this article to that on the Urinary System is necessary. It will here be convenient to take up the development at the stage depicted in the accompanying figure (fig. 7), in which the genital ridge (a) is seen on each side of the attachment of the mesentery; external to this, and forming another slight ridge of its own, is the Wolffian duct, while a little later the Miillerian duct is formed and lies ventral to the Wolffian. The early history of these ducts is indicated in the article on the Urinary System. Until the fifth or sixth week the development of the genital ridge is very much the same in the two sexes, and consists of cords of cells growing from the epithelium-covered surface into the mesenchyme, which forms the interior of the ridge. In these cords are some large germ cells which are distinguishable at a very early stage of development. It must, of course, be understood that the germinal epithelium covering the ridge, and the mesenchyme inside it, are both derived from the mesoderm or middle layer of the embryo. About the fifth week of human embryonic life the tunica albuginea appears in the male, from which septa grow to divide the testis into lobules, while the epithelial cords form the seminiferous tubes, though these do not gain a lumen until just before puberty. From the adjacent mesonephros cords of cells grow into the attached part of the genital ridge, or testis, as it now is, and from these the rete testis is developed. Recent research, however, points to these cords of the rete testis et ovarii as being derived from the coelomic epithelium instead of from the mesonephros.

In the female the same growth of epithelial cords into the mesenchyme of the genital ridge takes place, but each one is Neural tube. .....

- Spinal ganglion -Spinal nerve Aorta- From A. F. Dixon, Cunningham's Text-Book of Anatomy. FIG. 7. - Transverse Section through a Rat Embryo a. shows position of germinal epithelium.

distinguished by a bulging toward its middle, in which alone the large germ cells are found. Eventually this bulging part is broken up into a series of small portions, each of which contains one germ cell or ovum, and gives rise to a Graafian follicle. Mesonephric cords appear as in the male; they do not enter the ovary, however, but form a transitory network (rete ovarii) in the mesovarium. As each genital gland enlarges it remains attached to the rest of the intermediate cell mass by a constricted fold of the coelomic membrane, known as the mesorchium in the male, and the mesovarium in the female. Lying dorsal to the genital ridge in the intermediate cell mass is the mesonephros, consisting FIG. 8. - Diagram of the Formation of the Genito-Urinary Apparatus. The first figure is the generalized type, the second the male and the third the female specialized arrangements. Suppressed parts are dotted.

N. Nephrostome.

M.C. Malpighian corpuscle.

T. Testis.

E. Epididymis.

O.U. Organ of Giraldes. V.D. Vas deferens. U.M. Uterus masculinus.

O. Ovary.

Ep.O. Epoophoron. Par.O. Paroophoron. F.T. Fallopian tube.

U. Uterus.

-Vein -`Wolffian-duct -- Intestine of numerous tubules which open into the Wolffian duct. This at first is an important excretory organ, but during development becomes used for other purposes. In the male, as has been shown, it may form the rete testis, and certainly forms the vasa efferentia and globus major of the epididymis: in addition to these, some of its separate tubes probably account for the vas aberrans and the organ of Giraldes (see fig. 8, E. and O.G.). In the female the tubules of the epodphoron represent the main part, Pronephros. Mesonephros. Metanephros. Bladder.

Cloaca.

Rectum.

Miillerian duct. Wolffian duct. Ureter.

Sessile hydatid. Pedunculated hydatid. Sexual gland.

Pro. N.

M.N.

Mt. N. B.

Clo.

M.D. W. D. Ur.

S.H.; P .H.

S. G.

inward to meet its fellow at the back of the bladder, just above the prostate. The whole length of the vas is 12 to 18 in. and it is remarkable for the great thickness of its muscular walls, which gives it the feeling of a piece of whipcord when rolled between the finger and thumb.

A little above the globus major a few scattered tubules are found in children in front of the cord; these form the rudimentary structure known as the organ of Giraldes or paradidymis. As the vas deferens approaches the prostate it enlarges and becomes slightly sacculated to act as a reservoir for the secretion of the testis; this part is the ampulla (see fig. 2).

Posterior superior iliac spine Ureter Great sciatic notch Vas deferens; Spine of ischium Vas deferens Seminal vesicle Bladder wall Levator ani Prostate 9, ? Ischio-rectal fossa Tuberosity of ischium Gluteus maximus The vesiculae seminales are sac-like diverticula, one on each side, from the lower part of the ampullae of the vasa deferentia. They are about 2 in. long and run outward behind the bladder and parallel to the upper margin of the prostate for some little distance, but usually turn upward near their blind extremity. When carefully dissected and unravelled each is found to consist of a thick tube, about 5 in. long, which is sharply bent upon itself two or three times, and also has several short, sac-like pouches or diverticula. The vesiculae seminales are muscular sacs with a mucous lining which is thrown into a series of delicate net-like folds. The convolutions are held together by the pelvic cellular tissue, and by involuntary muscle continuous with that of the bladder. It is probable that these vesicles are not reservoirs, as was at one time thought, but form some special secretion which mixes with that of the testes. Where the vesiculae join the ampullae of the vasa deferentia the ejaculatory ducts are formed; these are narrow and thin-walled, and run, side by side, through the prostate to open into the floor of the prostatic urethra.

The prostate is partly a muscular and partly a glandular structure, situated just below the bladder and traversed by the urethra; it is of a somewhat conical form with the base upward in contact with the bladder. Both vertically and transversely it measures about an inch and a quarter, while antero-posteriorly it is only about three-quarters of an inch, though its size is liable to great variation. It is enclosed in a fibrous capsule from which it is separated by the prostatic plexus of veins anteriorly. It is often described as formed of three lobes two lateral and a median or posterior, but careful sections and recent research throw doubt on the existence of the last.

Microscopically the prostate consists of masses of long, slender, slightly branching glands, embedded in unstriped muscle and fibrous tissue; these glands open by delicate ducts (about twenty in number) into the prostatic urethra, which will be.

described later. In the anterior part of the gland are seen bundles of striped muscle fibres, which are of interest when the comparative ana Ampulla of vas deferens tomy of the gland Cut end of great sacrois studied: they are 1 sciatic ligament Common ejaculatory duct Levator ani than in old prostates.

The male urethra begins at the bladder and runs through the prostate and perineum to the penis, which it traverses as far as the tip. It is divided into a prostatic, membranous and spongy part, and is altogether about 8 inches in length. The prostatic urethra runs downward through the prostate rather nearer the anterior than the pos terior part. It is about an inch and a quarter long, and in the middle of the gland it bends forward forming an angle (see fig. 5); here it is from a third to half an inch wide, though at the base and apex of the prostate it is narrower. When it is slit open from in front a longitudinal ridge is seen in its posterior wall, which is called the verumontanum or crista urethra, and on each side of this is a longitudinal depression, the prostatic sinus, into which numerous ducts of the prostate open, though some of them open on to the antero-lateral surface. Near the lower part of the verumontanum is a little pouch, the utriculus masculinus, about one-eighth of an inch deep, the opening of which is guarded by a delicate membranous circular fold, the male hymen. Close to the opening of the utriculus the ejaculatory ducts, already mentioned, open into the urethra by very small apertures. The part of the urethra above the openings of these ducts really belongs to the urinary system only, though it is convenient to describe it here. After leaving From A. F. Dixon, Cunningham's Text-book of Anatomy. FIG. 2. - View of the Base of the Bladder, Prostate, Seminal Vesicles and Vasa Deferentia from behind.

The coccyx and the sacro-sciatic ligaments, together with the muscles attached to them, have been removed. The levatores ani have been separated along the median raphe, and drawn outwards. A considerable portion of the rectum and the upper part of the right seminal vesicle have been taken away.

Posterior superior iliac spine Cut end of rectum Apex of sacrum Great sciatic notch Ureter Peritoneum Spine of ischium Bladder wall Seminal vesicle Tuberosity of ischium Ischio-rectal fossa Cut end of rectum External sphincter ani Gluteus maximus better seen in young the prostate the urethra runs more forward for about threequarters of an inch, lying between the two layers of the triangular From C. S. Wallace's Prostatic Enlargement. FIG. 4. - Transverse Section of a young Prostate, showing wavy striped muscle in front, urethra in the middle, and the two ejaculatory ducts behind.

(external meatus) a vertical slit. Into the whole length of the urethra mucous glands (glands of Littre) open, and in the roof of 1 Figs. 3, 4, 5 and 9 of this article are redrawn from Cuthbert S. Wallace's Prostatic Enlargement by permission of the managers of The Oxford Medical Publications.

the fossa navicularis the mouth of one of these is sometimes so large that it may engage the point of a small catheter and is known as the lacuna magna. As a rule the meatus is the narrowest part of the whole canal.

Opening into the spongy urethra where it passes through the bulb are the ducts of two small glands known as Cowper's glands, which lie on each side of the membranous urethra and are best seen in childhood.

The penis is the intromittent organ of generation, and is made up of three cylinders of erectile tissue, covered by skin and subcutaneous tissue without fat. In a transverse section two of these cylinders (the corpora cavernosa) are placed above, side by side, while one, the corpus spongiosum, is below. Posteriorly, at what is known as the root of the penis, the two corpora cavernosa diverge, become more and more fibrous in structure, and are attached on each side to the rami of the ischium, while the corpus spongiosum becomes more vascular and enlarges to form the bulb. It has already been pointed out that the whole length of the corpus spongiosum is traversed by the urethra. The anterior part of the penis is formed by the glans, a bell-shaped structure, apparently continuous with the corpus spongiosum, and having the conical ends of the corpora cavernosa fitted into depressions on its posterior surface. On the dorsum of the penis the rim of the bell-shaped glans projects beyond the level of the corpora cavernosa, and is From C. S. Wallace's Prostatie Enlargement. FIG. 5. - Sagittal Median Section of Bladder, Prostate and Rectum, showing one of the ejaculatory ducts.

known as the corona glandis. The skin of the penis forms a fold which covers the glans and is known as the prepuce or foreskin; when this is drawn back a median fold, the frenuluni praeputii, is seen running to just below the meatus. After forming the prepuce the skin is reflected over the .glans and here looks like mucbus membrane. The structure of the corpora cavernosa consists of a strong fibrous coat, the tunica albuginea, from the deep surface of which numerous fibrous trabeculae penetrate the interior and divide it into a number of spaces which are lined with endothelium and communicate with the veins. Between the two corpora cavernosa the sheath is not complete and, having a comb-like appearance, is known as the septum pectinatum. The structure of the corpus spongiosum and glans resembles that of the corpora cavernosa, but the trabeculae are finer and the network closer.

Female Reproductive Organs. The ovary is an organ which in shape and size somewhat resembles a large almond, though its appearance varies considerably in different individuals, and at different times of life. It lies in the side wall of the pelvis with its long axis nearly vertical and having its blunt end (tubal pole) upward. Its more pointed lower end iš attached to the uterus by the ligament of the ovary, while its anterior border has a short reflection of peritoneum, known as the mesovarium, running forward to the broad ligament of the uterus. It is through this anterior border that the vessels and nerves enter and leave the gland.

Under the microscope the ovary is seen to be covered by a FIG. 3. - Coronal Section through the Pelvis, showing the relations of the bladder above, prostate and bulb below.

ligament, both of which it pierces. This is known as the membranous urethra, and is very narrow, being gripped by the compressor urethrae muscle.

[HISTORY

The spongy urethra is that part which is enclosed in the penis after piercing the anterior layer of the triangular ligament. At first it lies in the substance of the bulb and, later, of the corpus spongiosum, while finally it passes through the glans. In the greater part of its course it is a transverse slit, but in traversing the glans it enlarges considerably to form the fossa navicularis, and here, in transverse section, it looks like an inverted T (1), then an inverted Y (A), and finally at its opening '-'uNtAT and Adolf (1806-1871), and his grandsons Johann Adolf and Oskar Philipp.

J. G. Repsold introduced essential improvements in the meridian circles by substituting microscopes (on Jesse Ramsden's plan) for the verniers to read the circles, and by making the various parts perfectly symmetrical. For a number of years the firm furnished meridian circles to the observatories at Hamburg, Konigsberg, Pulkova, &c.; later on its activity declined, while Pistor and Martins of Berlin rose to eminence. But after the discontinuance of this firm that of Repsold again came to the front, not only in the construction of transit circles, but also of equatorial mountings and more especially of heliometers (see Micrometer) .

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