You may be looking for "The Science of Oneness" as per the discussion here:
Walter Rawls, who worked with the effects of monopolar magnetic fields on matter with the late Albert Roy Davis, told me in a telephone conversation of his experiments with a North pole magnet situated over the pineal gland.
A mask was made which held the North pole end of a long cylindrical magnet over the pineal gland. The purpose was to stimulate the gland and see if there was anything to this ‘third eye’ business. Exposure was in the range of 10-30 minutes per day over a period of about 4 weeks.
Within the first week, he was sitting at his desk reading documents when he noticed something move out of the corner of his eye. As he looked up, the ghostly figure of a man had walked through one wall, moved across the room and disappeared through another wall. The figure was totally unaware of Walter. Further exposures to this North pole field took place over a second and third week.
The second week, the same ghostly figure moved through the room and glanced toward Walter as he passed through. This time, the figure appeared to have slightly more detail, not quite so ghostly.
The third week, while busy working on documents, Walter noticed a change in the room. When he looked up, the wall had dissolved away and he was looking at a small hill where a man and woman sat beneath a tree. It was the same ghostly male figure who he had seen on the other occasions. He sat quit still, watching this pastoral scene for several minutes.
The man looked over toward Walter and appeared startled. It was as if he clearly SAW Walter this time and possibly recognized Walter as the ghost that he had seen the previous week! The image faded away and the wall restored to its normal condition. From that moment on, Walter never used the pineal stimulator again.
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science fiction "magnet * forehead" pineal gland