A few days later a modest little ad appeared in the weekly publication "What to do in Marsport." It did not try to compete with any of the casino ads (all of which featured pretty girls), but it had a unique heading.

FREE
For the First Time Ever
Your HOROSCOPE
SCIENTIFICALLY CAST
by the Staff of the
FAMOUS MARS OBSERVATORY
Learn your Luck, your Future!
Write or call Mars Observatory.
No charge. No obligation.

Since the horoscopes being offered were about the only things on Mars that didn't cost the tourists any money, the response was great. The recipient of a horoscope found a mimeographed folder which contained three pages describing the present positions of the planets, where to look for Earth in the sky, and what science hoped to learn the next time Mercury was in transit. The fourth page held the kicker. It said that while the tourist's luck would be better than average at most of the gambling houses, he would lose consistently if he played at Harvey's Club.

Within two days the only people playing at Harvey's were the shills. The following day, the visitors to the observatory included Harvey.

The gambler was welcomed with mi............