Boy or girl?

There are various theories on how to influence the sex of a baby. Here is a link.

What I found amazing was the following:
...No matter how silly some of these techniques seem, spare a thought for the French in the 18th century. It was widely believed that if a man tied off his left testicle, a boy would be more likely. The theory was based on the mistaken belief that sperm from each testicle were sex-specific.