If you were serious about producing a male heir around the turn of the 20th century, there was plenty of questionable advice to follow.

1. SCIENCE IS FOR THE UNIMAGINATIVE

First, it's important that we understand how human bodies select gender in reproduction. This is best accomplished through peer-reviewed scientific studies in a clinical environment. Or not. Sometimes you just know in your gut how reproductive microbiology works. Laura Davis, who wrote The Law of Sex Determination and Its Practical Application in 1916, didn't need egghead science. She learned about ovaries and spermatozoa in the school of life:

The writer is not in a position to furnish absolute verification, through methods of anatomy or physiology, of her theory. She has no laboratories nor methods of precision by which her theory can be directly tested. But she is convinced of its truth from her own extensive experience in its practical application for a period of thirty years.

Argue with that, if you dare. It is through this extensive experience that Davis feels confident to share with you her secret. If you want a boy, it all depends on which ovary you decide to use.

2. PICK AN OVARY

According to Davis, "Sex of the embryo in man and the higher animals is determined in the ovary from which the ovum in question is developed." She continued:

In the normal female the ovary of the right side yields ova which on fertilization develop as males, and the ovary of the left side yields ova which are potentially female. To this end the influence of gravitation can be utilized. In order that fertilizing spermatozoa shall reach the right or left ovary, it is necessary that gravity should carry them in the direction desired.

Therefore Davis would counsel women who wanted a boy to lie on their right sides. Percy John McElrath, who wrote The Key to Sex Control in 1911, also believed gravity was important to conception:

After insemination she should lie for three or four hours on the side of the ovary which matured the ovum; if it is not known which ovary matured the ovum, she should choose the most comfortable side to lie on and remain on that side for five or six hours to assist by gravity the ovum to the fimbriae extremity of the Fallopian tube.

If society — or, say, his own personal sense of professionalism — had permitted Mr. McElrath to actually talk to a female in this era, he might have learned most women are hard-pressed to know "which ovary" they excreted an egg out of. Similarly, Mr. McElrath would be unlikely to know which of his testicles produced the most virile sperm. (Although he had a solution for that, as we shall soon see.)

3. ENFEEBLE YOURSELF

Henri Médile Gourrier, writing in 1886, didn't think gravity or even ovaries mattered when it came to having a son. Gender was determined by whichever parent was the most feeble:

If marked symptoms of debility exist on the side of the sex that is desired, this sex will be produced naturally, without any effort being made.

Therefore, if a man wanted a boy, he must set about handicapping himself with what Gourrier called "The Debilitating Regimen":

This is the most essential. The food should consist of thin soups, white meats, such as veal, chicken, and lamb; mucilaginous articles of diet, such as corn starch and pastries; also vegetables and, in summer, fruits. For drink, in addition to water, weak tea may be taken with the meals. If a person desires to attain a still greater degree of debility, it is necessary to restrict the diet, to perform manual labor, and to bathe frequently in warm water.

So … in the 19th century one "debilitated" oneself by eating lean meats and vegetables, performing physical exercise, and taking warm baths. Somebody needs to tell all those people down at the gym the havoc they are wreaking on their bodies. If they continue that way, extensive bloodletting with an unwashed nail might be the only way for them to regain their health.

If the basic Debilitating Regimen did not result in a son, Gourrier permitted his readers to exercise even harder and then have some wine:

Then, finally, if this course does not suffice, aperient drinks should be taken, and the exercise of the body should be carried to fatigue.

Even better than the above methods was the Disease Method. The absolute best time to conceive a child of your own sex is on the immediate heels of any horrendous illness:

The period of convalescence from acute diseases. It is at such times that the senses and the generative organs, recovering from their somnolence, commence to shake off their inertia, and to come out of their inaptitude; that the fatigued body, that the depressed and enfeebled economy, finds itself in the most favorable condition for generation and for producing its own sex, both at the same time.

So, if you want a son, see if you can catch yourself a stout case of measles or any of the finer poxes. If you survive that, you and your wife are just one half-conscious encounter of life-sapping love away from a son.

4. DON'T BLAME DAD

Simon Newcomb, writing in 1904, made an earnest effort to reveal the mysteries of sex selection by using the most crafty of all deceits — statistics. His analysis of the birth records from 1900 yielded these conclusions:

Your body doesn't know what's going on, either:

The sex is not absolutely determined at any one moment or by any one act, but is the product of a series of accidental causes, some acting in one direction and some in another, until preponderance in one direction finally determines it. The statistics of twins and triplets seem to show very strongly that these accidents occur after conception, but throw no light upon the question of the time which they occupy.

Dad's got almost nothing to do with it:

The most natural inference from all the statistical data is that the functions of the father in generation are entirely asexual, the sex being determined wholly by the mother. If so, it cannot be said that one father is more likely than another to have children of either sex.

5. ORGASMIC RUPTURES!

Percy John McElrath may not have known much about women, but he was sure he knew how to get them produce a son. He believed sons resulted specifically from the intervention of the Graafian follicle in the ovary. You had to rupture it early to get a son, and the best way to do that was a well-timed orgasm.

Male-Production. — The spermatozoon must reach the ovum before it becomes old and female-producing. To do this it is necessary to inseminate at a time when orgasm of the female will rupture the Graafian follicle. Orgasm in the female will probably rupture a follicle from three to five days sooner than it would if allowed to burst of its own accord. It is better not to cohabit after the election date of insemination, inasmuch as orgasm of the female is liable to expel the fertilized ovum before it has become attached to the wall of the uterus.

McElrath's theory was the opposite of Gourrier's. It was the robustness of a father, not his feebleness, which produced a son, so he gave special instructions to men on how to strengthen themselves. Key factors: potatoes, stay away from women, and flush those testicles daily!

To prepare the male for the production of a fine male child, he should go on a starch diet for two or three months prior to the anticipated insemination, work hard and constantly, remain secluded from the female, see that the clothing is loose about the testicles and that they are not subjected to any pressure just five or six days before the anticipated date of insemination. The semen should be ejected once each day for four or five days before insemination. This will insure the presence of the very best specimens of spermatozoa and at the same time require more activity on the part of the male to reach orgasm and will assist the female to orgasm.

To sum up Mr. McElrath's approach to gender determination: Avoid women, both before and after conception. They are mythical creatures constantly trembling on the edge of orgasm, able to control their ovulatory system at will. Also, don't forget to masturbate. That way, if you're lucky, you'll only have to have sex once to ensure the propagation of the glory of manhood.

It's important to remember that, for the most part, these people weren't idiots. They were ambitious and tried to figure out something they didn't understand with the little information they could collect. In 100 years, our great-great-grandchildren will no doubt be raising eyebrows at us, and how we had no clue most diseases are caused by a chemical secreted by house cats when they get their feelings hurt.

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