Its influence is eternally mysterious. Exposure to it has variously been credited with removing freckles and warts and curing leprosy. And it has been blamed for causing everything from madness to blindness. 'It' is the moon. And its real or imagined effects on mankind have been remarked upon from time immemorial. Ancient Jewish teachings warn against certain activities in the moonlight. Ancient Greeks thought the full moon was a lucky time to marry. Even today, the moon remains mysterious. If anything is as constant as the moon's phases for instance, it is man's superstitions about the effects of the full moon. Perhaps it is more than superstition. You can judge for yourself, since there is a full moon this very night. But full-moon lunacy is attested to by many who have to deal with it from hospital workers to law-enforcement officers. It's difficult to say anything with certainty about the effects of the full moon. At least one researcher suggests that magnetic interaction between the Earth and moon affects the minerals in the human body. Others suggest, less convincingly, that if the moon can turn the tides it can also affect the human body, which is 80% water. Both new moons and full moons occur when the sun, moon, and Earth are lined up. In a full moon, the Earth is between the moon and the sun, so the moon's surface appears awash in sunlight. New moons occur when the moon is between the sun and Earth. The far side of the moon is bathed in sunlight, while the side facing the Earth is dark. During both full and new moons, ocean tides are at their highest. Some theories about the moon have waxed and waned over the years. By far the most prevalent theories are those linking full moons to bizarre behavior, increased illness, or even accelerated birth rates. In Chicago, Ralph Morris, a professor at the University of Illinois College of Pharmacy, says his research 'indicates a correlation between the week of the full moon and a greater incidence of bleeding ulcer attacks, as well as coronary attacks in angina patients.' He concludes that 'stress-related diseases are most likely to have their crises, whether behavioral or physical.' Some researchers are reluctant to discuss their lunar-linked findings lest they be considered astrologers or alchemists. Indeed some early alchemists prescribed bloodletting based on the phases of the moon, and some scientists think today's moon lore is just as suspect. 'We haven't found anything that shows an increase in admissions or an increase of referrals at the time of the full moon,' says Edwin Robbins, associate director of psychiatry at Bellevue Hospital Center in New York. 'We studied this for many years,' he adds. 'I never wrote it up, because it's so stupid.' But that is unlikely to convince those who have observed the lunacy of man and beast. Toni Garcia, a former security guard at the San Diego Zoo, says elephants are more often frolic in their swimming pools on full-moon evenings. Contrary to myth, however, the zoo's wolves don't howl at the moon-full or otherwise, she says. Men are another story. When the moon is full, says Mark Hews, a driver with Park Cadillac Limousine Service in Palm Beach, Florida, 'people tend to be crazier.' He adds, 'Maybe they drink too much. A lot of weird things seem to happen on full moons.' Which of the following is mentioned as a fact in the passage?