Of the Nails.
From whence do nails proceed?
Of the fumosity and humours, which are resolved and go into the extremities of the fingers, and they are dried through the power of the external air, and brought to the hardness of a horn.
Why do the nails of old men grow black and pale?
Because the heat of the heart decayeth, which decaying, their beauty decayeth also.
Why are men judged to be good or evil complexioned by the colour of their nails?
Because they give witness of the goodness or badness of the heart, and therefore of the complexion; for if they be somewhat red, they betoken choler well tempered; but if they be yellowish or black they signify melancholy.
Why do white spots appear in the nails?
Through mixture of phlegm with the nutriment.