After these incidents the "mineral club" kept its instruments in operation until June 1951, but nothing more was recorded. And, curiously enough, during this period while the radiation level remained normal, the visual sightings in the area dropped off too. The "mineral club" decided to concentrate on determining the significance of the data they had obtained. Accordingly, the scientist and the group made a detailed study of their mountaintop findings. They had friends working on many research projects throughout the United States and managed to visit and confer with them while on business trips. They investigated the possibility of unusual sunspot activity, but sunspots had been normal during the brief periods of high radiation. To clinch the elimination of sunspots as a cause, their record tapes showed no burst of radiation when sunspot activity had been abnormal. The "rock hounds" checked every possible research project that might have produced some stray radiation for their instruments to pick up. They found nothing. They checked and rechecked their instruments, but could find no factor that might have induced false readings. They let other scientists in on their findings, hoping that these outsiders might be able to put their fingers on errors that had been overlooked. Now, more than a year after the occurrence of the mysterious incidents that they had recorded, a year spent in analyzing their data, the "rock hounds" had no answer. By the best scientific tests that they had been able to apply, the visual sightings and the high radiation had taken place more or less simultaneously. Intriguing ideas are hard to kill, and this one had more than one life, possibly because of the element of mystery which surrounds the subject of flying saucers. But the scientific mind thrives on taking the mystery out of unexplained events, so it is not surprising that the investigation went on. According to my friend the scientist, a few people outside the laboratory where the "rock hounds" worked were told about the activities of the "mineral club," and they started radiation- detection groups of their own. For instance, two graduate astronomy students from a southwestern university started a similar watch, on a modest scale, using a modified standard Geiger counter as their detection unit. They did not build a recorder into their equipment, however, and consequently were forced to man their equipment continuously, which naturally cut down the time they were in operation. On two occasions they reportedly detected a burst of high radiation. Although the veracity of the two astronomers was not doubted, the scientist felt that the accuracy of their readings was poor because of the rather low quality of their equipment.