[73e]
all of bone.
And bone He compounded in this wise. Having sifted earth till it was pure and smooth, He kneaded it and moistened it with marrow; then He placed it in fire, and after that dipped it in water, and from this back to fire, and once again in water; and by thus transferring it many times from the one element to the other He made it so that it was soluble by neither. This, then, He used, and fashioned thereof, by turning, a bony sphere round about the brain; and therein he left a narrow opening; and around the marrow