The Semen is a yellowish-white liquid substance secreted in the Testes of the Male, and which contains the animalculÆ that grow to be future human beings. A microscopic examination shows it to consist of two substances, one fluid and the other little white globules. These globules soon dissolve when exposed to the air. The composition of the Semen is nine-tenths water—the remaining tenth being 10 soda, 30 phosphate of lime, and 60 animal mucilage containing a peculiar principle which is unknown. The living animalculÆ of the Semen can be plainly seen with a microscope. They look like little eels with large heads, or pollywogs, and are supposed to be the germ of the brain and spine. They are called Zoospermes, and the microscope enables us to study their habits, and describe them with correctness. These animalculÆ first grow in the little globules or eggs. Their extreme smallness may be imagined when we state that one of these globules, which are not visible to the naked eye, but can be seen only with a microscope, contains thirty of them. After the globules break open, the Zoospermes grow and become developed before they are in a fit state to enter the female Ovum. Attached to their head is a sort of sucker which fastens itself on to anything it can take hold of. By the aid of the microscope we are enabled to study the habits of these animalculÆ so closely that it is known they cast their skins as they grow larger, like some insects. A French physiologist writes that he easily distinguishes their sex, male and female, but we doubt the truth of his assertion. They are apparently very playful and active, but it appears to be their nature to move only in one direction, and that straight forward—which movement has a connection with impregnation that is explained elsewhere in these pages. In watching the motions of these curious little creatures, we find that combats frequently occur among them. They fight very fiercely, and sometimes the fight lasts until only one or two out of a dozen or more are left alive, showing a pugnacity of disposition peculiar to mankind in the primitive or half-civilized state. They will live for several hours in warm water, and it is thus that their manoeuvres are more easily seen. The Semen of a boy, before puberty, contains no Zoospermes; and hence females of amorous propensities have indulged with them without becoming impregnated. Diseases of a certain character, and also some kinds of drugs, will destroy the vitality of the Semen.

The animalculÆ of the Semen are not developed in the Testes. While there, it contains only the granules, which ripen as they proceed, and it is not until they reach the Prostate Gland that they burst open. It is therefore necessary to a healthy connection, that some time should elapse between the acts of coition. It frequently happens, when people first marry, that months will pass before impregnation takes place. This is because of too frequent connection. The Semen does not have time to be fully developed on its passage from the Testes.

We have stated that it is a habit of the Zoospermes to move only in one direction, and that straight forward. It is this peculiarity which enables them to make their way up into the Womb, even from the Labia or external lips of the female. It is found, also, that Zoospermes will live twenty-four hours in the private parts of the female, during which time she may become impregnated by them. It seems to be of little consequence how Semen is deposited in the female organ. Conception may take place, even without sexual connection, if the Semen is fresh from the male, and healthy. The sexual feeling of the female, though it may conduce certain favorable conditions of the part, and thus promote the result, is not, in most cases, necessary.

The celebrated John Hunter reported the case of a patient of his who had entirely lost his penis by syphilis. It was sloughed off half an inch into his body. Yet this man could eject his semen from the orifice; and he married after his misfortune, and became the father of a child. His wife was impregnated by means of a small glass syringe, with which the semen was injected into the proper place.

The Parisian doctors make preparations of various drugs to destroy the animalculÆ of the Semen, and thus prevent conception. This plan, if thoroughly adopted, produces the desired effect, as will be shown hereafter. Iodine, Strychnine, Prussic Acid, or even Opium, will instantly kill the Zoospermes. Alcohol will likewise generally destroy them, or render them powerless until they die. An electric shock kills them instantly, and so will cold water, in very many cases, though not always.

Modern science enables us to speak with certainty relative to a cause of childless couples, which is a want of vitality of the Semen. Formerly it was supposed that barrenness was a peculiarity of women alone; but it is now known that the fault is more frequently in the husband. The Semen of these barren men contains the usual globules, which never ripen or come to maturity. Such men may experience a certain degree of pleasure in connection, but they cannot become fathers. The Semen is undeveloped, like that of a boy of ten years. The sexual desires of such men are never very strong, and quickly subside; nor can they excite the female to any great degree of ardor. Long continued excesses in venery, whether with women or by means of onanism, is a frequent cause of barrenness or impotence in men. In these cases the Semen loses its prolific power. Frequently this impotence cannot be remedied, though I have cured many persons of it who had daily involuntary emissions of the spermatic fluid without erections or amorous impulse. The treatment consists in avoiding its causes, restoring the general health by proper diet and exercise, and in invigorating the affected organs by the internal and external use of such remedies as have a direct influence upon them.