https://github.com/davepinch/pinchy.cc/blob/master/content/topics/works/h/henry-woldmar-ruoff/universal-manual-of-ready-reference/archive.org.md
REM sleep is the deepest possible level of ordinary sleep and involves complete disengagement of the body’s motor cortex functions from the neck down and nearly complete suppression of consciousness in the Left brain hemisphere.
New Century Book of Facts (Wikipedia) The New Century Book of Facts was a single volume general reference work published in the United States from 1909 to 1964.