sequent erection supervene sooner or later. Pills of the crumb of bread, and a recommendation to the individual not to approach his wife for a fortnight, whatever may be his desire, have in almost all cases removed the impotence.

The state of erection is not long maintained, except under unusual excitement; the organ soon returning to its ordinary flaccidity.

Its cause is evidently a congestion of blood in the erectile tissue of the corpora cavernosa, urethra, and glans. Swammerdam and De Graaf cut off the penis of a dog during erection, and found the tissue gorged with blood, and that the organ returned to its flaccid condition, as the blood flowed from it. The same fact, according to Adelon, has been observed in the human subject, where erection has continued till after death. Mr. Callaway, of Guy's Hospital, London, has described the case of an individual, who, in a state of inebriation, had communication three times with his wife the same night, without the consequent collapse succeeding, although emission ensued each time. This condition persisted for sixteen days, notwithstanding the use of the appropriate means: at this time, an opening was made with a lancet in the left crus of the penis, below the scrotum, and a large quantity of dark, grumous blood, with numerous small coagula, escaped. By pressing the penis, the corpora cavernosa were immediately emptied, and each side became flaccid; the communication by the pecten, or septum penis, permitting the discharge of the contents of both corpora by the incision into the left crus. After recovery, the person remained quite impotent, the organ being incapable of erection, owing, as Mr. Callaway judiciously suggests, to the deposition of coagulable lymph in the cells of the corpora cavernosa preventing the admission of blood, and the consequent distention of the organ.

Artificial erection can, likewise, be induced in the dead body by injections, so that but little doubt need exist, that the enlargement and rigidity of the penis, during erection, are caused by the larger quantity of blood sent into it.

The great difficulty has been, to account for this increased flow. The older writers ascribed it to the compression of the internal pudic vein against the symphysis pubis, owing to the organ being raised towards the abdomen by the ischio-cavernosi muscles; and as the cavernous vein empties its blood into the internal pudic, stagnation of blood in the corpora cavernosa ought necessarily to result from such compression, and consequent distention of the organ; whilst the cavernous arteries, being firmer, would not yield to the compression, and would, therefore, continue to convey the blood to the penis.

It is obvious, however, that here, as in every case, where the erectile tissue is concerned,—the congestion must be of an active kind: the beating of the arteries and the coloration of the organ in

dicate this; and, besides, it is not possible, that any compression of the pudic vein can precede erection; it must, if it occur at all, be regarded rather as a consequence of erection than as its cause. The case of the female nipple affords us an instance of erectility, where no compression can be invoked, and where the distention must be caused by augmented flow of blood by the arteries. If the nipple be handled, particularly whilst the female is under voluptuous excitement, it will be found to enlarge, and to become rigid, or to be in a true state of erection. The common opinion, amongst physiologists, is, that irritation of this erectile tissue is the first link in the chain of phenomena constituting erection. The feeling of pleasure is certainly experienced there, prior to, and during, erection; and this irritation, like every other, solicits an increased flow of blood into the erectile tissue, which, by organization, is capable of considerable distention.

The erectile tissues of the corpora cavernosa, and of the corpus spongiosum urethræ, and glans, are all concerned in the process, but in what precise manner physiologists are not entirely agreed. Some have supposed, that the blood is effused into the cells, and is consequently out of the vessels. Another view, supported by some of the most eminent anatomists and physiologists is, that the blood simply accumulates in the venous plexuses of the corpora cavernosa. Such seems to have been the inference of Cuvier, Chaussier, and Beclard, from their injections; and the rapidity, with which erection disappears, favours the notion.

It has been asked, again, whether this accumulation of blood be, as we have remarked, an increased afflux by the arteries, or a diminished action of the veins; or these two states combined. The last opinion is probably the most correct. The arteries first respond to the appeal; the organ is, at the same time, raised by the appropriate muscles; its tissue becomes distended, the plexus of veins becomes turgid, and the return of blood impeded. In this way, the organ acquires the rigidity, necessary for penetrating the parts of the female. The friction which then occurs, keeps up the voluptuous excitement and the state of erection. This excitement is extended to the whole generative system; the secretion of the testicle is augmented; the sperm arrives in greater quantity in the vesiculæ seminales; the testicles are drawn up towards the abdominal rings by the contraction of the dartos and cremaster, so that the vas deferens is rendered shorter, and, in the opinion of some, the sperm, filling the excretory ducts of the testicle is, in this manner, forced mechanically forwards towards the vesicles. When these have attained a certain degree of distention they contract suddenly and powerfully, and the sperm is projected through the ejaculatory ducts into the urethra. It is at this period, that the pleasurable sensation is at its height. When the sperm reaches the urethra, the canal is thrown into the highest excitement;

the ischio-cavernosi and bulbo-cavernosi muscles, with the transversus perinei, and levator ani are thrown into violent contraction; the two first holding the penis straight, and assisting the others in projecting the sperm along the urethra. By the agency of these muscles and of the proper muscular structure of the urethra, the fluid is expelled, not continuously, but in jets, as it seems to be sent into the urethra by the alternate contractions of the vesiculæ seminales.

The quantity of sperm, discharged, varies materially according to the circumstances previously mentioned; its average is estimated at about two drachms.

Along with the true sperm, the fluids of the prostate and of the glands of Cowper are discharged; so as to constitute the semen as we meet with it. When the emission is accomplished, the penis gradually returns to its ordinary state of flaccidity; and it is usually impracticable, by any effort, to repeat the act without the intervention of a certain interval of repose, to enable the due quantity of sperm to collect in the spermatic vessels and vesicles. In some persons, however, the excitability is so great, and the secretion of sperm so ready, that no interval is required between the first and second attempt.

This comprises the whole of the agency of the male in the function of generation.

In man, the emission of sperm is soon effected; but in certain animals it is a long process. In the dog, which has no vesiculæ seminales, the penis swells so much, during copulation, that it cannot be withdrawn until the emission of sperm removes the erection.

In the female, during copulation, the clitoris is in the same state of erection as the penis; as well as the spongy tissue, lining more especially the entrance of the vagina, and it is in these parts, particularly in the clitoris, that pleasure is experienced during sexual desire, and during copulation. This feeling persists the whole time of coition, and ultimately attains its acme, as in the case of the male, but without any spermatic ejaculation. It is not owing to the contact of the male sperm,--for it frequently occurs before or after emission by the male,—but is dependent upon some inappreciable modification in the female organs,—in the ovaries or Fallopian tubes, it is supposed by some physiologists. In most cases, an increased discharge takes place from the mucous follicles of the vagina and vulva; but this appears to be gradual, during the progress of coition, and in nowise to resemble the ejaculation of the male. After the kind of convulsive excitement into which the female is thrown, a sensation of languor and debility is experienced, as in the male, but not to the same extent,—and in consequence of no spermatic emission taking place in her, she is capable of a renewal of intercourse more speedily than the male, and can better support its frequent repetition.

An admixture having, in this manner, been effected between the materials furnished by the male and those of the female, after a fecundating copulation conception or fecundation results, and the rudiments of the new being are instantaneously constituted. The well-known fact, that, after the removal of the testicles, the individual is incapable of procreation, although the rest of the genital organs may remain entire, is of itself sufficient to show, that the fecundating fluid is the secretion of those organs, and that this fluid is indispensable. Physiologists have not, however, been satisfied with this fact. Spallanzani examined frogs with great attention, whilst in the act of copulation both in and out of water; and he observed, that, at the moment when the female deposited her eggs, the male darted a transparent liquor through a tumid point which issued from its anus. This liquor moistened the eggs, and fecundated them. To be certain that it was the fecundating agent, he dressed the male in waxed taffeta breeches; when he found that fecundation was prevented, and that sperm enough was contained in the breeches to be collected. This he took up by means of a camel's-hair pencil, and all the eggs, which he touched with it, were fecundated. Three grains of this sperm were sufficient to render a pound of water fecundating; and a drop of this solution, which could not contain more than the 2,994,687-500th part of a grain was enough for the purpose.

To diminish the objection, that the frog is too remote in organization from man to admit of any analogical deduction, SPALLANZANI took a spaniel bitch, which had engendered several times; shut her up some time before the period of heat, and waited until she exhibited evidences of being in that condition, which did not happen until after twenty-three days of seclusion. He then injected into the vagina and uterus, by means of a common syringe warmed to 100° of Fahrenheit, nineteen grains of sperm obtained from a dog. Two days afterwards she ceased to be in heat, and, at the ordinary period, she brought forth three young ones, which not only resembled her but the dog from which the sperm had been obtained. This experiment has been repeated by Rossi of Pisa, and by Buffolini of Cesena, with similar results.

In some experiments on generation, Prevost and Dumas fecundated artificially the ova of the frog. Having expressed the fluid from several testicles, and diluted it with water, they placed the ova in it. These were observed to become tumid and developed; whilst other ova, placed in common water, merely swelled up, and in a few days became putrid. They observed, moreover, that the mucus, with which the ova are covered in the oviduct, -the part corresponding to the Fallopian tube in the mammalia,— assists in the absorption of the sperm, and in conducting it to the surface of the ovum; and that, in order to succeed in these artificial fecundations, the sperm must be diluted. If too much concentrated its action is less. They satisfied themselves, likewise,

that the chief part of the sperm penetrates as far as the ova, as animalcules could be detected moving in the mucus covering their surface, and these animalcules they conceive to be the active part of the sperm.

It is not, however, universally admitted, that the positive contact of the sperm with the ovum is indispensable to fecundation. Some physiologists maintain, that the sperm proceeds no farther than the upper part of the vagina; whence, according to some, it is absorbed by the vessels of that canal, and conveyed through the circulation to the ovary. This is, however, the most improbable of all the views that have been indulged on this topic; for if such were the fact, impregnation ought to be effected as easily by injecting sperm into the blood-vessels, the female being, at the time, in a state of voluptuous excitement. Others have presumed, that when the sperm is thrown into the vagina, a halitus or aurathe aura seminis—escapes from it, makes its way to the ovary, and impregnates an ovum. Others, again, think that the sperm is projected into the uterus, and that in this cavity it undergoes admixture with the germ furnished by the female; whilst a last class, with more probability in their favour, maintain that the sperm is thrown into the uterus, whence it passes through the Fallopian tube to the ovary, the fimbriated extremity of the tube, at the time, embracing the latter organ.

Dr. Dewees,—the able adjunct professor of midwifery in the University of Pennsylvania,—has suggested, that after the sperm is deposited on the labia pudendi or in the vagina, it may be taken up by a set of vessels,—which, he admits, have never been seen in the human female—whose duty it is to convey the sperm to the ovary. This conjecture he conceives to have been in part confirmed, by the discovery of ducts, leading from the ovary to the vagina, in the cow and sow, by Dr. Gartner of Copenhagen. The objections that may be urged against his hypothesis, Dr. DEWEES remarks, "he must leave to others." We have no doubt, that his intimate acquaintance with the subject could have suggested many that are pertinent and cogent. It will be obvious, that if we admit the existence of the ducts, described by Gartner, it by no means follows, that they arc certainly inservient to the function in question. Independently, too, of the objection, that they have not been met with in the human female, it may be urged, that if we grant their existence, there would seem to be no reason, why closure of the os uteri after impregnation, or division of the Fallopian tubes, should prevent subsequent conception, in the former case during the existence of pregnancy, in the latter, for life. These vessels ought, in both cases, to continue to convey sperm to the ovary, and extra-uterine pregnancies or superfœtation ought to be constantly occurring.

MM. Prevost and Dumas are the most recent writers, who VOL. II.

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