4952. CONCERNING A PLACE WHERE PEOPLE GROW INSANE WHEN THEY LOOK WITHIN. There is a place at the back, near the lower part of the spinal marrow, into which when people put the head they began to grow so stupefied that they suffered acute pain, feeling, that they were almost destitute of intellectual life. Some put their heads therein and such a thing happened to them. They were removed thence lest they should disturb this sphere. But [the place] was afterwards closed up. The closing up appeared like as if a pestle were flung into a great siphon.