A lover should not hold his bride by the ears. Clergy men should not be fed on the choicest delicacies lest their other "appetite" be inflamed. A four-leaf clover slipped into a man's shoe will make him forever adore the woman who placed it there.

If you didn't know these simple rules pertaining to sex, manners and morals, it is because you haven't learned from the past - but there is still time to take a quick course.

A woman can learn the almost forgotten secret of Hesse and Oldenburg, where many a man's heart was captured by a girl who cleverly cut her finger and allowed a few drops of blood to mingles with his glass of beer. (In Bohemia, bat's blood could be used by any who flinched from pain - and had a supply of bats.)

Men can still be saved from the tragedy of marrying a woman with a forehead shaped like their own. And parents can be reminded that it is dangerous to whip children lest they come to like it.

This lore is contained in "This was Sex," a collection by Sandy Teller of advice available in the late 19th and early 20th centuries on subjects now the province of advisers from Playboy and Penthouse.The advice comes from an era in which there was come action in moviehouses than on their screens, but it shares one mind - set with much of today's advice - it is written, in the main, for men.

The playboy, however, is the arch villain of whom all good company must beware. "Compared with his crime, murder is innocence. Even hanging forever would be too good for him," the author of "Sexual Science" states of the Seducer.

But just when everything seems clear, the author of "Sexual Ethics: A Study of Borderland Questions" counsels men that it is not always easy to tell whether a woman's resistance is feigned or real.

"Whether the use of a certain degree of violence will arouse the most ardent passion of love, or the most furious anger . . . whether he will find himself in paradise or in the penitentiary," is a question on which the reader receives no clear instruction.

Other subjects were easier for our ancestors' advisers.

To lose weight, women are told to have lots of children drink squawvine tea and sleep sparingly.

Saloons, wrote James Foster Scott, who practiced medicine in the District of Columbia, are "the very light-houses of hell."

In this corsetless age it is a relief to read that we are free of one damnable habit. Tight-lacing, it was said, was more destructive than those other destructive hyphenated habits: tobacco-chewing, liquor-drinking and pork-eating.

One adviser hazarded the theory that it was because of their tightly corseted waists that women screamed when they saw a mouse. Although is research data are weak, it is true that today's unlaced women don't do much screaming at mice.

Teller has chosen from a wide variety of sources.

You can learn everything from why women aren't good at clapping their hands to the dangers of having sex soon after eating.

There is even a motto for young men: "The mind away from sexual thoughts and the hands away from the parts."